I actually have what's called a PXP3, which basically is Sega's Genesis/PSP crossover knockoff.
It still has 4 buttons instead of 6 (X & Z excluded in my underatanding) so that doesn't help in any way.
I've actually just completed MK for my very 1st time, it was just on very easy and set to six kredits.
One thing: It's weird how after you either win or lose the game, after *this* screen the game doesn't restart and instead the screen blacks out to this creepy bass growling noise and it stays that way until you restart the PXP3 system.