OK, I renamed mysetup.DK to mysetup_.DK. There was no interface.bbw.

I restarted BiaB as admin. Windows asked if that is OK, I said yes.

BiaB started and asked if I wanted to associate BiaB files with Windows Explorer. Never had that dialog before. I said no.

I opened Midi setup, pressed OK - no change.
"BiaB has stopped working".

I hope Support comes up with some suggestions.

I wanna start playing already!