that's great you got it worked out! I'm considering this exact setup, except for choice in tire. It good to know a square 245 will work for rs3s. Did you consider zIIs, or rivals? Does anyone know if they run wider?
2010 128i manual, sport package, performance exhaust, Vorshlag camber plates, 245/45/17 ZII square on et 40 with rolled rear fenders.