Do you have a mechanical way of altering the cam sensor? Ie is it in a distributor that you can turn for example?

If you can alter it a little and reset the sync values, this may well get rid of the problem, as I have seen similar when the sync isnt in the right range (it quotes the desired optimum in the manual, I dont have it to hand but its something like 50 or so IIRC)

As everyone else has said, take it to Mark as he is the UK distributor for the Autronic so will be in a position of having seen more with errors wether that be hardware or config than anyone else in the country, and as you have already had him do some work on the car it makes even more sense.

How come you are running on an external map sensor not the internal one? They are 4 bar sensors anyway so perfectly well suited to a car running 2 bar of boost or a little more.