Working and non-working system versions

[probonopd]

Since this is using a Macintosh Plus ROM, what is limiting this emulation from running later versions of the system software?

Working

• system-3.2-finder-5.3-system-tools-1.0-512-ke-jun-1986-3.5-800k

Not working

• system-4.3-finder-6.0-system-software-5.1-nov-1987 (System error "ID = 15")

Probably just needs more RAM than 208K:

ID=15 Segment Loader Error
Macintosh programs are broken up into segments, and each program will always have at least one segment. Multiple segments allow loading parts of the program into memory to provide more room for data in internal RAM. The segment loader is responsible for loading a needed segment into RAM. If the segment loader can't do this, you'll see this error.

[evansm7]

Aside from not being able to use infinite memory, it’s umac. Ie how about test things out using umac built for your Linux box or similar?

I ran 6 on umac, 7.5.5 also. I haven’t made a list!