Cool! I improved my ROM transcription code a bit, so it's probably catching a few more mistakes. I still manually check each bit as well, but that gets pretty tiresome, especially with these 4K chips.
I put some info about Total Control 4 on my TMS1400 page- www.seanriddle.com/tms1400.html, but I won't have the ROM dump or the full hardware description until next week at the earliest.