Some of these skins install in the GBA section of Delta. You need special ROMs that are compiled in a .GBA format that have the systems ROMs in the .GBA file. If you dont have these or know how to compile them you can ask around on the
and someone can help you. Skins will be listed as "For Modified GBA ROMS" if they need modified GBA ROMS. Other skins work in the Sega Genesis section of Delta.