So I rebooted my PC and it started working again. I realised that ScratchCrumble must have been running in some sort of diagnostic mode since previously it was continually reporting the state of the inputs whereas now it does not and last line of text from the bootup report just says “msgs running”.
The sensor value drop down now has A B C D at the bottom again. Previously they were not there
So now it seems to be OK but I will play with it for a bit longer to see if it holds up. Previously when I started trying out the other inputs (b,c,& d)was when it started to get flaky…