Not to sure if this has been posted before but I found a very useful article on repairing scuff marks and scrathes on alloy wheels.
http://www.autopia-carcare.com/realwhda.html
My mate used this to fix some damage on his car and it looks brand new.
But instead of using that special laquar he used normal silver & clear coat paint.

Just thought I'd share this with you!

Michael.