Thought I would give everyone an update and finalise this thread.
I had the car to a good auto electrician last week. He checked out the electrical side of the VVL lift system and he confirmed there is no faulty wiring. The system is functioning BUT the stepper motor although cycling, will not calibrate between the two end stops. He suggested it was a mechanical fault and not electrical so back home it came.
I bit the bullet and ordered a new eccentric valvetronic shaft as I knew the teeth on the end cog were worn as previously discussed.
spent 4 hours today stripping down and fitting it and retiming the cams back up.
All back together, cycled the ignition a few times to calibrate it and started the car.
bingo. Everything working fine and all fault codes gone. Car driving brilliant.
so it appears that because of the wear to the gear and associated backlash on the motor it simply can’t calibrate itself so completely shuts the ecu down only allowing the car to start but only sit at idle. Amazing.
hope this helps anyone in the future. Thanks for everyone’s suggestions.