First of all, I am impressed of the emulator. fucking great job.
Due to myself, I may have a hint on why the starwars-scroller in the Sidmania demo by Censor is wacky and aswell as make the snes9x unstable.
I think the copiers we used had more save-ram and we stored pre-calculated data for the rotating of the mode-7 scroller in the demo.
Isn't 32Kb max for SRAM?
I was involved in an FX game, and if I don't remember wrong we did have trouble fitting double buffered graphics there.
Anyhow, that may also make isnes9x crash as the snes code reads/writes data from maybe not allocated memory of you, or just some other system.
So, just make a bigger alloc for the SRAM and it may stabalize my fuckups 18 years ago.
PS.
I don't know if 32K was maximum SRAM, I do remember using loads of SRAM.
I wouldn't be suprised we had 128K.
http://www.pouet.net/prod.php?which=2462
/Che