It is interesting how what worked flawlessly on the hardware of the time is almost impossible to get to work on these emulators, the fidelity is quite low. But bit by bit I'm making progress in figuring out where the differences are and how to work around them. I've got a basic self-hosted development system working now with all of the data in a ram disk. The floppy, keyboard and VGA screen all work, now I need to figure out why the harddrive controller keeps disappearing.
Oh well, the night is young ;)
Thank you for posting this! It really moved the needle in what already was a super long debug session.