68040 library?

[Matt_H]

Are you using a recent DOpus, as in 4.16 or 4.17? The older, commercial releases in the 4.11 neighborhood are somewhat crashy on high-end hardware.

[Matt_H]

You can get 4.17p21 here, but 4.16 should be sufficiently stable. Strange. Make sure the supporting modules (DOpus.library, etc.) come from the same archive as the executable.

The 1200 doesn't have a ROM Speed jumper, so no worries there.

Check if SnoopDOS outputs anything interesting. Also try starting DOpus with no config file (rename the current one to something else for testing purposes)

I think someone else mentioned SetPatch. This is what you should be using on 3.1 or below (3.5 and above have a newer version built in).