Thanks for all the responses. The one point that I find hard to understand is that one I have finally stopped and switch off then turn back on the ignition it all fires up ok. If it was say a dodgy earth then maybe it could still be in a "fault" position and not start?
Another quirk on this car compared to the S1 is when you start up all lights, etc show up on the dash ie the headlight full beam, the gauges ramp up and then down etc. Is this a way the car "checks" its systems or is this a possible pointer for the fault issue?
thanks
T