Hi 180,
I guess I missed this post. Yes, I agree with Pizzaguy, you likely have a problem with the wire feeding pin 8 - it should be at battery voltage. Also, 0.75 ohms seems high for ground, but that could be your meter. Have you connected your leads together to see what the resistance of just the leads are? If that's high then okay, but if thats low, like less than 0.1 ohms (hopefully, more like 0.01ohms). I don't know if you would feel comfortable doing this, but you can short pin 49 on the BCM to ground or wire your door switch directly to pin 49 (i.e., connect a wire from pin 49 to pin 8 of the door switch, and connect pin 4 of the door switch to ground. Now you have bypassed the wiring, and hopefully the door switch will work normally). If you connect pin 49 to ground, I would think you'll get my results, and confirm it's the wire between pin 49 and pin 8 that's your issue.
Good Luck,
-Jerry