[pothole]

Update:

I now think this is a problem related to the door lock microswitch(es). Having done some research, it seems Porsche used a VW part for this, so hopefully I will be able to source a new lock mechanism without paying Porsche tax (the microswitch inside the mechanism is fixable, but it' a bit complex, so think if I can source a new mechanism for a decent price, I will do that).