i think i also have similar issues with my wheels. They kind of look like dripping water marks and spots. The are like greyish / whitish in color i guess. I get them all the time when i try to use wheels cleaners. I used neverdull to take it off and it worked perfectly... Take a shot at it...
they have it at autozone and other car part stores..
Current: 2010 AW/BLK 135i Mods: G5 ISO, Wedge Backend, DCI, BMS DPs, VRSF CP, TIAL BOV, Big Tom, Meth, Fuel-It Stage 2, BMW PE
Best so far 12.5 @ 19.46 spinning all the way down
VM 6465 waiting to be installed. Relationship status is changing soon