Can’t seem to get this to work. There’s no core input options in the retroarch menu so I can’t save a remap file. If I change any buttons in the mame “TAB” menu they don’t save when I relaunch the game. If I edit the button configs in the config file located at /opt/retropie/configs/mame-libretro/retroarch.cfg the changes don’t seem to load when I launch a game.
I just fixed this today :) Reinstall lr-mame2003 from source and any remaps you do via the tab key (mame internal menu) should save. also anything you do in the service menu (F2) should save also.
that said, anything you do in the retroarch.cfg should work also?