Edit 2: Okay so it actually loaded this time. It was either the fact that my SD Card was in the Lock position (my gawd im dumb), or I pressed a button on the black screen. Who knows, hopefully it works, not sure if I wanna risk doing the RPX version...
I'm pretty pro at Wii hacking but all new to Wii U. I'll mainly use it for nes/sega/snes/gameboy games. I assume genesisGX core runs Sega CD games fine, how about 32x? Hows n64/ps1 compatbility, through wiisx/not64 on wii compatibility was somwhat decent)
Genplus GX does not support 32X unfortunately, we will have to wait for a Picodrive core, which may be some time, but fingers crossed! Ditto N64 and PS1: hopefully soon! Just run those through wiisx/not64 for the time being (you can always play them on vWii), or N64 VC which runs a few games via injection.