@agranlund Trying EMUTOS now...
This one is pretty bizarre as well. I'm using your 4K MAPROM test PRGs. long story short, the "Cache" versions don't work with EMUTOS. Seems to stop the floppy drive from working. The "non-Cache" version works fine.
Not really sure if EMUTOS copies lower ROM variables automatically into alt-ram anyway ? think that maybe only copying ROM into alt-ram may be useful for EMUTOS ?
Current scores.
EMUTOS 1.1.1 - MAP4K - MAPROM.PRG (no ST-RAM caches enabled in MAPROM) and blitter not fitted.

- IMG_0511.JPG (64.44 KiB) Viewed 2448 times
Bizarrely EMUTOS seems to totally block the blitter from working

it shows up in TOS206 and works fine. Also odd EMUTOS resets if I change resolution with the blitter installed. I also am not entirely sure if BLITFIX is needed for EMUTOS ?
TOS206 - MAP4K - MAPROM_C.PRG - BLITFIX.PRG - BLITTER ON

- IMG_0512.JPG (64.57 KiB) Viewed 2448 times
TOS206 - MAP4K - MAPROM_C.PRG - BLITFIX.PRG - BLITTER OFF

- IMG_0513.JPG (61.64 KiB) Viewed 2448 times
So the bottom line as it stands is that :
EMUTOS doesn't like ST-RAM caches enabled and does not like the blitter fitted.
TOS206 works fine with the blitter and cached ST-RAM, but the desktop caches need to be turned off if using the floppy drive.