It's something rather wrong with the display (at least those are the symptoms, although I can't remember exactly what it did do wrong). It appeared to work for a short while, then went funny. I tried reseating everything I could poke, without much luck, which is where I stopped, my electronic knowledge being pretty minimal. I'd like to get Elite A on it, only ever played that version on an emulator.
Hmm, there's a thought. Could an emulator be written for this board to run native Beeb stuff rather faster than it's supposed to go?