Its interesting about the 7-pin vs 6-pin connector. I noticed that the factory tail light had just 6 pins, but the new Taiwan/China light has 7 pins. I had a similar issue with mine, so thanks for clarifying why my tail light was not working correctly.
You don't have to rewire these chinese lights. The rear light on the drivers side that you rewired was a rear fog light, and the right one rear fog light doesn't have a pin in a plug because european requirements doesn't require it in right hand traffic.