I know that the original SuperGen (external) required modification to be compatible with AGA machines. But the SuperGen plugs right into the Amiga's RGB port... I don't know how these Hama genlocks connect.
I don't know what made the SuperGen incompatible or how one can tell it's not working. Mine already had the mod.
Maybe there is some small difference on the RGB port of a 500/2000 than on a 1200/4000?
good luck,
trilobyte