In reply to CJE
You are correct: it was not using project SIMON.
It was in 256 colours, which someone there suggested might, actually, be slower than, say, a 32 thousand colour mode. (Something to do with 256 being emulated ?)
But the part of Adjust-32e to display 32 thousand colours is not in place yet.
In rely to Chris
I also asked who designed and who made the circuit boards to which the cryptic reply was, "A range of sources".
I was thinking 'Simtec' but they stonewalled on that one.