Hi Sarah,
I bought a blueflame exhaust around 6 months ago and ended up selling it again as I had a similar problem to you (I have a One and the exhaust was made for a Cooper S). It came without the hangers and the standard Cooper S hangers that I got hold of weren't up to the job as they were rather ill fitting. The other problem that I faced was that my car only had the bracket underneath for one of the rear boxes (drivers side) and the other box required a bracket on the passenger side of the car. I think you can get hold of the bracket(s) from a dealer as I went down and queried it (can't think of the part number sorry), but I'd recommend going to an exhaust fabricator to get some custom hangers made up.
I couldn't be bothered going to all that hassle and it's probably not what you want to hear but I hope that helps?
Iain
