@AtariHERO Sorry about this requirement, the game handles the data and music files separately hence the requirement in the code. I will try to remove this issue when I can.
As already clarified, all non-psm files should be upper case (name and extension), all psm files should be lowercase. Currently if files are not found it is noted in the logfile (available by turning on Output logs in the GMenu2x settings screen then by running Log Viewer from settings which is only present after running the app).
@Gab1975 I'd not noticed the white bar issue, should be easy to fix. EDIT it's related to palette changes, on world 2 the bar is pink for example. EDIT Fixed, uploaded