Here are some instructions on how to activate the upgrade key on a clean install: http://forums.mydigitallife.info/threads/21142-upgrade-key-on-clean-install-(pre-and-post-install-workaround)
This is for Win7, but I think it should also work for Win8 (some people have reported that it worked...
Damn, I signed up for a $14.99 coupon with fake data (I didn't really buy a Windows 7 machine a while ago) and bought Win8, and now after reading that someone reported a problem, I'm scared that I might've wasted those $14.99 :(
So what's the latest on this? Has anyone recently used the $14.99...