diff --git a/src/activities/railroad/Railroad.qml b/src/activities/railroad/Railroad.qml
index 019f3087c..3550f0705 100644
--- a/src/activities/railroad/Railroad.qml
+++ b/src/activities/railroad/Railroad.qml
@@ -1,593 +1,593 @@
 /* GCompris - railroad.qml
  *
  * Copyright (C) 2016 Utkarsh Tiwari <iamutkarshtiwari@kde.org>
  * Copyright (C) 2018 Amit Sagtani <asagtani06@gmail.com>
  *
  * Authors:
  *   Pascal Georges (GTK+ version)
  *   Utkarsh Tiwari <iamutkarshtiwari@kde.org> (Qt Quick port)
  *   Amit Sagtani <asagtani06@gmail.com> (Qt Quick port)
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
  *   the Free Software Foundation; either version 3 of the License, or
  *   (at your option) any later version.
  *
  *   This program is distributed in the hope that it will be useful,
  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *   GNU General Public License for more details.
  *
  *   You should have received a copy of the GNU General Public License
  *   along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 import QtQuick 2.6
 import GCompris 1.0
 import "../../core"
 import "railroad.js" as Activity
 
 ActivityBase {
     id: activity
 
     onStart: focus = true
     onStop: {}
 
     pageComponent: Image {
         id: background
         source: Activity.resourceURL + "railroad-bg.svg"
         height: activity.height / 2
         width: activity.width
         anchors.fill: parent
 
         signal start
         signal stop
 
         Component.onCompleted: {
             activity.start.connect(start)
             activity.stop.connect(stop)
         }
 
         // Add here the QML items you need to access in javascript
         QtObject {
             id: items
             property Item main: activity.main
             property alias background: background
             property alias bar: bar
             property alias bonus: bonus
             property alias score: score
             property alias trainAnimationTimer: trainAnimationTimer
             property alias sampleList: sampleList
             property alias listModel: listModel
             property alias answerZone: answerZone
             property alias animateFlow: animateFlow
             property alias introMessage: introMessage
             property bool memoryMode: false
             property bool mouseEnabled: true
             property var currentKeyZone: sampleList
             property bool keyNavigationMode: false
             // stores height of sampleGrid images to set rail bar support position
             property int sampleImageHeight: 0
         }
 
         onStart: { Activity.start(items) }
         onStop: { Activity.stop() }
         Keys.enabled: !trainAnimationTimer.running && !animateFlow.running && !introMessage.visible
         Keys.onPressed: {
             items.keyNavigationMode = true;
             items.currentKeyZone.handleKeys(event);
             activity.audioEffects.play('qrc:/gcompris/src/core/resource/sounds/smudge.wav');
         }
 
         // Countdown timer
         Timer {
             id: trainAnimationTimer
             repeat: false
             interval: 4000
             onTriggered: {
                 items.animateFlow.start()
                 activity.audioEffects.play(Activity.resourceURL + 'sounds/train.wav')
             }
         }
 
         // Intro message
         IntroMessage {
             id: introMessage
             y: background.height / 4.7
             anchors {
                 right: parent.right
                 rightMargin: 5
                 left: parent.left
                 leftMargin: 5
             }
             z: score.z + 1
             onIntroDone: {
                 trainAnimationTimer.start()
             }
             intro: [
                 qsTr("Observe and remember the train before the timer ends and then drag the items to set up a similar train."),
                 qsTr("If you forget the positions, you can click on the Hint button to view them again.")
             ]
         }
 
         // Top Display Area
         Rectangle {
             id: topDisplayArea
             width: background.width
             height: background.height / 4.5
             y: background.height / 12.7
             color: 'transparent'
             z: 1
 
             GridView {
                 id: answerZone
                 readonly property int levelCellWidth: (background.width > background.height) ? background.width / (listModel.count > 5 ? 7.2 : 5.66) :
                                                                                                background.width / ((listModel.count > 5) ? 7.1 : 5)
                 readonly property int levelCellHeight: background.width > background.height ? topDisplayArea.height / 2 : topDisplayArea.height / 3
                 width: parent.width
                 height: background.height / 8
                 cellWidth: levelCellWidth
                 cellHeight: levelCellHeight
                 y: background.width > background.height ? sampleList.y - height * 1.55 : sampleList.y - height * 1.29
                 interactive: false
                 model: listModel
                 delegate: Image {
                     id: wagon
                     source: Activity.resourceURL + modelData + ".svg"
                     height: answerZone.levelCellHeight
                     width: answerZone.levelCellWidth
                     sourceSize.width: width
                     function checkDrop(dragItem) {
                         // Checks the drop location of this wagon
                         var globalCoordinates = dragItem.mapToItem(answerZone, 0, 0)
                         if(globalCoordinates.y <= ((background.height / 12.5) + (background.height / 8))) {
                             var dropIndex = Activity.getDropIndex(globalCoordinates.x)
 
                             if(dropIndex > (listModel.count - 1)) {
                                 // Handles index overflow
                                 dropIndex = listModel.count - 1
                             }
                             listModel.move(listModel.count - 1, dropIndex, 1)
                             opacity = 1
                         }
                         if(globalCoordinates.y > (background.height / 8)) {
                             // Remove it if dropped in the lower section
                             activity.audioEffects.play('qrc:/gcompris/src/core/resource/sounds/smudge.wav')
                             listModel.remove(listModel.count - 1)
                         }
                     }
 
                     function createNewItem() {
                         var component = Qt.createComponent("Loco.qml");
                         if(component.status === Component.Ready) {
                             var newItem = component.createObject(parent, {"x": x, "y": y, "z": 10, "imageURL": source});
                         }
                         return newItem
                     }
 
                     MouseArea {
                         id: displayWagonMouseArea
                         hoverEnabled: true
                         enabled: !introMessage.visible && items.mouseEnabled
                         anchors.fill: parent
 
                         onPressed: {
                             if(items.memoryMode) {
                                 drag.target = parent.createNewItem();
                                 parent.opacity = 0
                                 listModel.move(index, listModel.count - 1, 1)
                             }
                             answerZone.selectedSwapIndex = -1;
                         }
                         onReleased: {
                             if(items.memoryMode) {
                                 var dragItem = drag.target
                                 parent.checkDrop(dragItem)
                                 dragItem.destroy();
                                 parent.Drag.cancel()
                             }
                         }
 
                         onClicked: {
                             // skips memorization time
                             if(!items.memoryMode) {
                                 bar.hintClicked()
                             }
                             else {
                                 items.currentKeyZone = answerZone
                                 if(items.keyNavigationMode) {
                                     answerZone.currentIndex = index
                                 }
                             }
                             answerZone.selectedSwapIndex = -1;
                         }
                     }
                     states: State {
                         name: "wagonHover"
                         when: displayWagonMouseArea.containsMouse && (items.memoryMode === true)
                         PropertyChanges {
                             target: wagon
                             scale: 1.1
                         }
                     }
                 }
 
                 onXChanged: {
                     if(answerZone.x >= background.width) {
                         trainAnimationTimer.stop()
                         animateFlow.stop();
                         listModel.clear();
                         items.memoryMode = true;
                     }
                 }
 
                 PropertyAnimation {
                     id: animateFlow
                     target: answerZone
                     properties: "x"
                     from: answerZone.x
                     to: background.width
                     duration: 4000
                     easing.type: Easing.InExpo
                     loops: 1
                     onStopped: answerZone.x = 2;
                 }
 
                 function handleKeys(event) {
                     // Switch zones via tab key.
                     if(event.key === Qt.Key_Tab) {
                         items.currentKeyZone = sampleList
                         sampleList.currentIndex = 0
                         answerZone.currentIndex = -1
                     }
                     if(event.key === Qt.Key_Down) {
                         items.currentKeyZone = sampleList
                         answerZone.currentIndex = -1
                         sampleList.currentIndex = 0
                     }
                     if(event.key === Qt.Key_Up) {
                         items.currentKeyZone = sampleList
                         answerZone.currentIndex = -1
                         sampleList.currentIndex = 0
                     }
                     if(event.key === Qt.Key_Left) {
                         items.currentKeyZone = answerZone
                         answerZone.moveCurrentIndexLeft()
                     }
                     if(event.key === Qt.Key_Right) {
                         items.currentKeyZone = answerZone
                         answerZone.moveCurrentIndexRight()
                     }
                     // Remove a wagon via Delete/Return key.
                     if(event.key === Qt.Key_Delete && listModel.count > 0) {
                         activity.audioEffects.play('qrc:/gcompris/src/core/resource/sounds/smudge.wav')
                         listModel.remove(answerZone.currentIndex)
                         if(listModel.count < 2) {
                             answerZone.selectedSwapIndex = -1;
                         }
                     }
                     // Checks answer.
                     if((event.key === Qt.Key_Return || event.key === Qt.Key_Enter) && items.mouseEnabled) {
                         items.currentKeyZone = answerZone
                         Activity.checkAnswer();
                     }
                     // Swaps two wagons with help of Space/Enter keys.
                     if(event.key === Qt.Key_Space) {
                         if(selectedSwapIndex === -1 && listModel.count > 1) {
                             answerZone.selectedSwapIndex = answerZone.currentIndex;
                             swapHighlight.x = answerZone.currentItem.x;
                             swapHighlight.anchors.top = answerZone.top;
                         }
                         else if(answerZone.currentIndex != selectedSwapIndex && listModel.count > 1){
                             var min = Math.min(selectedSwapIndex, answerZone.currentIndex);
                             var max = Math.max(selectedSwapIndex, answerZone.currentIndex);
                             listModel.move(min, max, 1);
                             listModel.move(max-1, min, 1);
                             answerZone.selectedSwapIndex = -1;
                         }
                     }
                 }
-                // variable for storing the index of wagons to be swaped via key navigations.
+                // variable for storing the index of wagons to be swapped via key navigations.
                 property int selectedSwapIndex: -1
 
                 Keys.enabled: true
                 focus: true
                 keyNavigationWraps: true
                 highlightRangeMode: GridView.ApplyRange
                 highlight: Rectangle {
                     width: answerZone.cellWidth
                     height: answerZone.cellHeight
                     color: "blue"
                     opacity: 0.3
                     radius: 5
                     visible: (items.currentKeyZone === answerZone) && (!trainAnimationTimer.running && !animateFlow.running) && items.keyNavigationMode
                     x: visible ? answerZone.currentItem.x : 0
                     y: visible ? answerZone.currentItem.y : 0
                     Behavior on x {
                         SpringAnimation {
                             spring: 3
                             damping: 0.2
                         }
                     }
                     Behavior on y {
                         SpringAnimation {
                             spring: 3
                             damping: 0.2
                         }
                     }
                 }
                 highlightFollowsCurrentItem: false
             }
 
             // Used to highlight a wagon selected for swaping via key navigations
             Rectangle {
                 id: swapHighlight
                 width: answerZone.cellWidth
                 height: answerZone.cellHeight
                 visible: answerZone.selectedSwapIndex != -1 ? true : false
                 color: "#AA41AAC4"
                 opacity: 0.8
                 radius: 5
             }
 
             ListModel {
                 id: listModel
             }
         }
 
         // Lower Sample Wagon Display Area
         GridView {
             id: sampleList
             visible: items.memoryMode
             y: background.height / 4.7
             z: 5
             width: background.width
             height: background.height - topDisplayArea.height
             anchors.margins: 20
             cellWidth: width / columnCount
             cellHeight: (background.width > background.height) ? background.height / 7 : background.height / 7.5
             model: Activity.dataset["noOfLocos"][bar.level - 1] + Activity.dataset["noOfWagons"][bar.level - 1]
             interactive: false
 
             // No. of wagons in a row
             readonly property int columnCount: (background.width > background.height) ? Activity.dataset["columnsInHorizontalMode"][bar.level - 1] :
         Activity.dataset["columsInVerticalMode"][bar.level - 1]
 
             readonly property int rowCount: columnCount > 0 ? model / columnCount : 0
 
             delegate: Image {
                 id: loco
                 readonly property string uniqueID: Activity.uniqueId[index]
                 property real originX
                 property real originY
                 source: Activity.resourceURL + uniqueID + ".svg"
                 width: (background.width > background.height) ? background.width / 5.66 : background.width / 4.2
                 sourceSize.width: width
                 fillMode: Image.PreserveAspectFit
                 visible: true
                 onHeightChanged: items.sampleImageHeight = height
                 onVisibleChanged: items.sampleImageHeight = height
                 function initDrag() {
                     originX = x
                     originY = y
                 }
 
                 function replace() {
                     x = originX
                     y = originY
                 }
 
                 function checkDrop() {
                     // Checks the drop location of this wagon
                     var globalCoordinates = loco.mapToItem(answerZone, 0, 0)
                     // checks if the wagon is dropped in correct zone and no. of wagons in answer row are less than
                     // total no. of wagons in correct answer + 2, before dropping the wagon
                     if(globalCoordinates.y <= (background.height / 12.5) &&
                             listModel.count < Activity.dataset["WagonsInCorrectAnswers"][bar.level - 1] + 2) {
                         activity.audioEffects.play('qrc:/gcompris/src/core/resource/sounds/smudge.wav')
                         var dropIndex = Activity.getDropIndex(globalCoordinates.x)
                         Activity.addWagon(uniqueID, dropIndex);
                     }
                 }
 
                 MouseArea {
                     id: mouseArea
                     hoverEnabled: true
                     anchors.fill: parent
                     drag.target: parent
                     enabled: items.mouseEnabled
                     onClicked: {
                         items.currentKeyZone = sampleList
                         if(items.keyNavigationMode) {
                             sampleList.currentIndex = index
                         }
                     }
                     onPressed: {
                         parent.initDrag()
                     }
                     onReleased: {
                         parent.Drag.cancel()
                         parent.checkDrop()
                         parent.replace()
                     }
                 }
 
                 Component.onCompleted: initDrag();
 
                 states: State {
                     name: "carHover"
                     when: mouseArea.containsMouse
                     PropertyChanges {
                         target: loco
                         scale: 1.1
                     }
                 }
             }
 
             function handleKeys(event) {
                 if(event.key === Qt.Key_Tab) {
                     if(listModel.count > 0) {
                         items.currentKeyZone = answerZone
                         sampleList.currentIndex = -1
                         answerZone.currentIndex = 0
                     }
                 }
                 if(event.key === Qt.Key_Up) {
                     items.currentKeyZone = sampleList
                     // Checks if current highlighted element is in first row of the grid.
                     if(sampleList.currentIndex < columnCount && listModel.count > 0) {
                         items.currentKeyZone = answerZone
                         answerZone.currentIndex = 0
                         sampleList.currentIndex = -1
                     }
                     else {
                         sampleList.moveCurrentIndexUp()
                     }
                 }
                 if(event.key === Qt.Key_Down) {
                     items.currentKeyZone = sampleList
                     sampleList.moveCurrentIndexDown()
                 }
                 if(event.key === Qt.Key_Left) {
                     items.currentKeyZone = sampleList
                     sampleList.moveCurrentIndexLeft()
                 }
                 if(event.key === Qt.Key_Right) {
                     items.currentKeyZone = sampleList
                     sampleList.moveCurrentIndexRight()
                 }
                 if(event.key === Qt.Key_Space) {
                     var imageId = Activity.uniqueId[sampleList.currentIndex]
                     // At most (current level + 2) wagons are allowed in answer row at a time.
                     if(listModel.count < Activity.dataset["WagonsInCorrectAnswers"][bar.level - 1] + 2) {
                         activity.audioEffects.play('qrc:/gcompris/src/core/resource/sounds/smudge.wav')
                         Activity.addWagon(imageId, listModel.count);
                     }
                 }
                 if((event.key === Qt.Key_Enter || event.key === Qt.Key_Return) && listModel.count > 0 && items.mouseEnabled) {
                     items.currentKeyZone = sampleList
                     Activity.checkAnswer()
                 }
             }
 
             Keys.enabled: true
             focus: true
             keyNavigationWraps: true
             highlightRangeMode: GridView.ApplyRange
             highlight: Rectangle {
                 width: (background.width > background.height) ? background.width / 5.66 : background.width / 4.2
                 height: background.width > background.height ? sampleList.cellHeight : sampleList.cellHeight / 1.65
                 color: "#AA41AAC4"
                 opacity: 0.8
                 radius: 5
                 visible: items.currentKeyZone === sampleList && items.keyNavigationMode
                 x: (sampleList.currentIndex >= 0) ? sampleList.currentItem.x : 0
                 y: (sampleList.currentIndex >= 0) ? sampleList.currentItem.y : 0
                 Behavior on x {
                     SpringAnimation {
                         spring: 3
                         damping: 0.2
                     }
                 }
                 Behavior on y {
                     SpringAnimation {
                         spring: 3
                         damping: 0.2
                     }
                 }
             }
             highlightFollowsCurrentItem: false
         }
 
         // Lower level wagons shelves
         Repeater {
             id: railSupporter
             model: sampleList.rowCount
             Rectangle {
                 x: 0
                 y: sampleList.y + (sampleList.cellHeight * (index + 1)) - (sampleList.cellHeight - items.sampleImageHeight)
                 z: 1
                 width: background.width
                 height: (background.width > background.height) ? 6 : 3
                 border.color: "#808180"
                 color: "transparent"
                 border.width: 4
             }
         }
 
         // Answer Submission button
         BarButton {
             id: okButton
             source: "qrc:/gcompris/src/core/resource/bar_ok.svg"
             width: height
             height: score.height
             sourceSize.width: width
             sourceSize.height: height
             anchors.top: score.top
             z: score.z
             anchors {
                 right: score.left
                 rightMargin: 10
             }
             ParticleSystemStarLoader {
                 id: okButtonParticles
                 clip: false
             }
             MouseArea {
                 id: okButtonMouseArea
                 anchors.fill: parent
                 enabled: !trainAnimationTimer.running && !animateFlow.running && listModel.count > 0 && items.mouseEnabled
                 onClicked: Activity.checkAnswer()
             }
         }
 
         DialogHelp {
             id: dialogHelp
             onClose: home()
         }
 
         Score {
             id: score
             fontSize: background.width > background.height ? internalTextComponent.smallSize : internalTextComponent.tinySize
             anchors.top: parent.top
             anchors.topMargin: 10 * ApplicationInfo.ratio
             anchors.right: parent.right
             anchors.leftMargin: 10 * ApplicationInfo.ratio
             anchors.bottom: undefined
             anchors.left: undefined
         }
 
         Bar {
             id: bar
             content: BarEnumContent { value: help | home | level | hint }
             onHelpClicked: {
                 displayDialog(dialogHelp)
             }
             z: introMessage.z
             onPreviousLevelClicked: Activity.previousLevel()
             onNextLevelClicked: Activity.nextLevel()
             onHomeClicked: activity.home()
             onHintClicked: {
                 if(!introMessage.visible && items.mouseEnabled) {
                     if(items.memoryMode == false) {
                         trainAnimationTimer.stop()
                         animateFlow.stop();
                         listModel.clear();
                         for(var index = 0; index < Activity.backupListModel.length; index++) {
                             Activity.addWagon(Activity.backupListModel[index], index);
                         }
                         items.memoryMode = true;
                         okButton.visible = true;
                     } else {
                         Activity.restoreLevel();
                         okButton.visible = false;
                     }
                 }
             }
         }
 
         Bonus {
             id: bonus
             Component.onCompleted: win.connect(Activity.nextSubLevel)
         }
     }
 }