Sadly it's not working at all on my R4 Clone (R4 III Upgrade I believe it's called). I get a white screen and loading with the YSMENU gives a loading error. Seems to be working decently on the DeSuME so far though.
EDIT: I managed to be able to battle, check through the menu, and save with no problem on DeSuME 0.96.
(provided by copy_zero of GBAtemp) if someone can please explain or lead me to a tutorial that may explain how to use this it will be very appreciative. :-/