Been too long since I replied to this but for anyone needing a follow up: I DID simply swap out the old, 24V door master switch panel with the cheap, new 12V version available in north america for about $20. Thankfully, it worked 50%!!!! Meaning: my driver door does go up and down and has now since I did this swap in 2019 whilst the passenger door is still stuck in the up / closed position. Been 2 years and I figure one working window is better than none. As for the rear ones, 50% there also.... the passenger rear works just fine whilst the driver one only works directly from the driver side / passenger door switch. The master panel on my driver door won't do a thing for it. 50% on the rear works for me too at this point.