I had something similar, the window would stick down randomly...usually when raining or miles from home.
I done soft resets, changed the door module and stripped and rebuilt the switch, even had a poxy reset done at the local specialist...a week later the same problem which came up as a canbus error when plugged into my mates Snap-On diagnostic machine...resetting again worked for a couple of days only.
By now rather disenchanted and around £200 out of pocket I gave up and wired the drivers motor directly using a separate aftermarket switch and pair of relays...works perfectly and the passenger window still functions from the otherwise useless lump in the drivers door.
You can take power from the door module so no need to try running cables back to the fusebox either.
This supply will be constant, but I have left my car unused for a fortnight with no ill effects and the switch LED merrily glowing away the whole time.
Sprint - 33 - Sprint - 33 - 155 - GTV - GTV - 156 - GT ...gone German for now though.