I have a 2010 clubman S chilli, and I have had so many problems with this car, even now it sits with another problem and cant drive it again this weekend - fed up with it actually.
A few problems ago - probably the start of all problems, was a major oil leak, where it had heavily leaked all over the driveway, and then all down through the diff etc. I am sure that this was the beginning of the so called Sludge in the engine and then the Super Knock problem.
I would get your mini to the dealer and have it checked before it leads to more sinister internal unseen engine problems - actually I now take my mini to a local motor repairer, who are very helpful, but dont have the equipment to do major repairs. They check the error codes first, then I go back to the BMW dealer, cause I dont trust the BMW service anymore, at least now I go with a list of the error codes. Hope your mini is sorted for you. cheers Tracy