Update! It's running again, with the help of my friend and MQB guru Meich!
1: old unit, dead (and dusty)
2: old next to new (and the perfect time to clean things)
3: where the old one was sitting
4: new unit, alive (and not coded yet)
5: after coding, still a lot of errors to be resolved
But hey! It's driving again!
Now all I have to do is do a basic setting of the steering system. Tried it several times yesterday, but wasn't succesful. This causes a domino-effect of errors:
No steering angle sensor calibration = no ESP = errors in braking system = no hybrid power recuperation.
But nothing that can't be managed!