Derek
Evidently your private mailbox is full, so here is the response to your question concerning the resolution to the problem I had with my wheels getting black blotches on them.
After some doing BMWUSA replaced all four wheels. I had to buy new tires since I have been told that the type tires used on these rims cannot be safely remounted. It didn't make a lot of difference to me since the original tires were pretty well worn.
BMWUSA's first response to me was that I had damaged the finish on the wheels by using an improper soap on them. After I told them that I had used the same soap on the wheels that I used on the paint, the paint still looks great, they said they wanted to have a service rep from Atlanta come look at them.
When the rep came to see the wheels he said they would like to give me a bottle of BMW wheel cleaner and see how the wheels do. At that point, I asked if the wheel cleaner was going to cause the silver paint to return that had obviously worn off. I also showed them a email from this site that said that they had replaced the wheels for a Florida customer with the same problems I was having. They had set a precedent for the replacement. After that very calm discussion he agreed to replace my wheels under warranty.
Good luck and feel free to use the emails on this site to support your request. BMW is obviously aware that there is a problem with the finish on these wheels. From my experience you will need them. They won't volunteer to replace the wheels but will do the right thing if pushed.