Changed to breeze dark look and feel which sets theme to "Breeze Dark", no longer get an error message because the file is actually "BreezeDark"
A LNF package can also ship its own fully custom color scheme that isn't system-wide installed, so perhaps this needs some additional changes later, such as "You are using 'whatever lnf package' which uses a custom color scheme.", instead of a warning/error message. (I knew that dumping all of that "Current" and "Default" logic would fall on my feet eventually :/)