@meleu well, the original controller i use, is a custom coded teensy in a gameboy project im making
I'm trying to set everything up, before i stick my pi zero in the case. the code i use for the gameboy custom controller, uses the d-pad as hat switch, and for some odd reason, the non lr emulators, wont detect my d-pad presses, but they will detect all my other buttons (a,b,select start). so, i decided to put that on hold, and look into the lr emulators, and started with gpsp... and thats where i came across the issue, with swapping controllers. initially, i spent days and hours, trying to get mame4all (non lr) to detect my dpad/hat switch and it wouldnt, and that mame4all runs games the fastest/smoothest for me.