Try to get a battery charger on the car and see if you can get the bluefin to work after that and put your stock map back on
I always use a charger to make sure the supply is strong enough while flashing the car, especially in the winter
I have had quite a few customer with the APR DP on the 2.0 TFSI going through MOT here in Denmark with no problems. That's with a 200 cell cat and they where doing fine and with good margin to the limit
How old is your car and how many miles is on it ?
Bulbs do get used, and it could be that yours are simply ready for a replacement. IMO the best color is the 4300-4500 kelvin. 6000 gets to blue and you loose some light with them as well
I think that you have answered your own question
I just had a S5 in the shop the other day where the customer had an APR exhaust fitted. He was very happy with it. Consumption was not that bad actually from a big V8
I had a customer here in Denmark with a Seat Leon Cupra with APR 2+ that used water meth and ran the 104 octane map.
Just make sure you do a little work with vcds when you install it and get the correct size nozzle. It should not pull a lot of timing running the 104 map with water meth but the...