So far quite a lot of the machine is working for me.
I'm currently having troubles reading/writing real disks. From the Professional Monitor attempting to format a disk results in all sectors ending up as "bad" when checking (the computer hangs there for 1-2 minutes before proceeding to the next track). Disk select, motor and step controls work. The KR1818VG93 gets 11.8V under load (had to adjust the coil to 22uH), problems stay the same with a MB8877. The drive/disks has been used reliably with my Pentagon in the past.

Otherwise Video & sound output, bootup, professional monitor, SMUC, keyboard, etc. are working.