When doing a fresh run of GCompris (rm -f ~/.cache/KDE/gcompris-qt/data2/* ~/.config/gcompris/gcompris-qt.conf) and downloading the wordset, it won't be taken in account until there is a restart of GCompris.
ApplicationSettings.wordset seems to not be set.

(as I'm currently reworking the download system, if you want to work on it, please discuss first)