My suspicion is that Power protection relay is ....
de-energizing, wonder why. Is it happening on every window/sunroof or only with one of them? If all of them, the question would be to determine if there is any reason to believe that ALL windows are going up with difficulty making excessive draw current in the window circuitry. If not, there may be some damage in the metering resistor at the General Module. It is a resistor inside the GM between terminals 4 and 5 of X332 wired in series with the windows circuits. When excessive voltage develops across it, (caused by excess current), the system is disconnected de-energizing Power protection relay. If soldering points of this resistor to the circuit board are damaged, it acts as a higher value resistor, producing excess voltage with normal current. If this is not the reason, the GM metering and comparing circuit may be damaged. Hard to tell though.
See this link to identify the relay (K15) and confirm my guess, also check relay for any damage.
http://www.bimmernut.com/~billr/images/rear%20fuses.jpg
Javier
Yes, both systems feed from ....
the Power Protection Relay K15. If the system is now permanently shut down, then I would suspect the relay itself, bad contact, bad connector contact, or even General module poor contact in pins 4 and 5 referred.
Javier