Thanks for your great work.
I just have bought my Cassiopeia 500 especially for Mame.

My requests (and my dreams) are:
Pacman working
Frogger working
Phoenix with sound
Scramble and Burgertime and Digdug fast enough with sound activated
Ckong with complete sound (sound is incomplete in the current build)
Sample support for simple games like Space invaders

If you need an audio guy to make small, Cassiopeia-optimized samples (8 bit, 8 khz?) for mame games, I would be happy to do it for you.

P.S. My not-so-realistic dream is Marble Madness. (I am the guy with the marble-homepage www.bodenstaendig.de/marble). Theoretically, I think it could be possible on day on a Cassiopeia if we use sample-sound.