@hoeveler If core input remapping doesn't work, you can either do a configuration override (per-game) or manually add the input configuration in a game dependent configuration file (explained also on the same page).

@bagel-le-stinky you are right, sorry, now i remember that you dont have to rename the chd-file, but have to put it in a folder named like the rom-file.
If you rename your chd file back it should work;)