Nice colour S3 mate!
As for the running in for the engine i would say keep the engine below 4000rpm for the first 300miles with no WOT (wide open throttle).
Then below 5000rpm with no WOT for the next 300miles.
Then after that keep it under 5000rpm and use WOT occasionally and after 1000miles just hoooooooon the hell out of it and enjoy the car.
Thats what roughly do at work when we have a brand new engine in the test cell.
Your engine will have already had a production line hot test on the production line which consists of about 2hrs running at various speed and loads so you can hooooon it from the start but i would break it in gently.
Oh and the car wax thing, if you really wanna look after your paint then get some wax made by chemical guys pete's 53, its simply awesome, its £25 for a small pot but goes very far, a pot would do about 10 A3's, i have used Autoglym, Mer, Megs wax but i have recently looked on detailingworld.com for tips and advice and those guys reccommend 'specailist' waxes for proper protection and thats where i read about Petes 53.