BTW, these scans show you what is possible. As long as you choose the color from current Audi range(in fact all Audi colors form last 20 years are available) NO problems at all.
Only choose really carefully since some combos will look akward or plain stupid...

There are almost same level of personalisation for interior as well but, my advice is to stick with Black leather and add seat inserts in different color with full stitching in matching color(example-full Black leather with seat inserts in Signal Orange with full stithing in Signal Orange)-that would look truly awsome IMHO and your R8 will still have good aftersale value...

Here is good example:
Exterior: Sattelbraun Perfeffekt/ Side Blades Carbon Sigma
Interior: Black leather with Sattelbraun seat inserts and full stitching in Sattelbrown, Carbon Sigma Interior trim...

Here is the pic of color stitching(and you get that nice real alu plate with Audi Exclusive singature on the doors).