I am seeing precisely this, when I attempt to run any of my own projects, which are built with Xojo. The screen shot indicating "what failed" is identical.
My workaround was to restore an older VM from backup, and this time decline to "upgrade" the VM on launch. I did not downgrade Fusion itself.
To this point I've only noted it with the Windows VM, with no issues on Linux and legacy macOS.
This is on 10.15.6 Catalina, with the supplemental update.