being that they don't have the same amount of pads, and is the 500 only compatible with the 1000 akai os or is it also compatible with jjos 1 ? (not os 2)
I use REX2MPC to convert Recycle files into MPC programs and it only has an export option for MPC 1000/2500 (2000/2000XL as well, but that's another story).
Never had a problem reading those files in my 500.