68K-versions works well on MorphOS (MOS has a built-in run-time 68K-compiler). There seems to be another issue.
I use (68K) fat95 3.11 form 10.08.2003 by Thorsten Jager.

Check following:

After booting system insert a disk. Then type in a shell

diskchange MS0: (notice: MS0 not MSO!!)

Can you see now flashing the busy-LED from the floppydrive? If yes,device works and MS0: is mounted.

If not:

What happens when starting MS0-mountlist manually by typing in a shell mount DEVS:Dosdrivers/MS0 ? If message MS0: Allready mounted appears, then mountlist works. If not, you should look for propper setting tooltypes in MS0-icon! Have you set anything to MS0-icon, as I wrote you in PM (as shown in picture)?