In what sense they don’t work?
Many of these old customs have the “loop ending” problem, that can be fixed in a variety of ways, but otherwise they work.
When converting with C3 CON Tools, make sure you choose the correct PAL/NTSC for your PS3 and select Type 3 encryption.
You are about to leave Rhythm Gaming World and access the external songs DB. While no song or file sold for commercially available videogames is hosted there and only fan generated content is allowed, Rhythm Gaming World has no direct control over the database and no files are hosted here. Alright, we had to made you aware of this, now you can visit the database!