After finally managing to start the car today, it was running fairly rough so I decided to run a diagnostic and found a few really odd issues as follows:
Voltage reading high on cylinder 2 - twice as high as the other three.
MAF reading all over the place.
Ok, so, I swapped the coils packs round - still same voltage fault. Changed the MAF, still same erratic readings!!!
I'm now completely stumped as VAG COM says there are NO FAULTS!!!
Another interesting thing found - switching between stock map and revo makes bugger all difference so I'm beginning to think that the revo map is causing all the problems!