You can also use QSettings method "bool contains(QString &key)" to check if the user has that value in transitions.ini. So if the user doesn't you disable that particular option. In this way if the user has an active theme which doen't have cssu settings (and he may have CSSU installed) your program doesn't crash: you can even add the cssu options to "fix" that theme transitions.ini, adding the values in the right group.