razo+r, and Minhal,
Thank you both so much for your help.
It seems that the Rudder allocation of my Extreme 3d pro does not, suddenly, recognise the rudder inputs. So Razo+r, you were of course right.
Added to this is the fact that the keyboard element of the Control Options seems to have disappeared. All sorts of funky stuff going down.
I fear that I smell a delete and a reinstall coming.