I've added one PIA to the prototype and changed the ROM address decoding so that the FLASH ROM is mapped to ROM0 and ROM1. I flashed the ROM with the dragon 32 ROM image and turned on. After a few false starts (I still had some ROM address lines tied low, and I initially tried to use all 3 ROM select lines to enable the ROM) it works!
This is a big step forward. Not useful yet, since there is no keyboard but I'm happy to see it runing the Dragon ROM.
Also no graphics modes since the VDG pins are hardwired. Only monocrhome output for the moment.