I know exactly how you feel! Electrical problems are a real nightmare. I've been kept busy by a few on my car..

A battery reset is obviously resetting all the control modules (ecu et al). Usage, on the other hand, is causing an excess load that makes a control module switch things off. There's a K40 module in the ecu box in the engine bay that is normally associated with these controls - you could check if all connections, etc are fine on it.

There's also a control unit under the rear seat (left side) that operates these things (minus the wipers). You could check the connections on it. However, you mention its only the front seats, doors, etc that have this problem(?). That may well mean a wire going from this module to the front of the cabin.

I'm sure its a loose/corroded connection somewhere along this link. Do you have the fuse box under/side of the dash on driver side? That normally houses various fuses for these functions. The loose or corroded connection might be close to this box.