I never actually had the exact problem you described, and everything updated on my system with no problems. The ipv6 error is because older rounters don't have this new tech installed into the firmware yet and yes I know all about it.
Seems to me that a firmware update of my Dlink gaming router would fix this ipv6 issue. I have had it disabled since day one but I thought you were describing a fix for it so that it wouldn't have to be disabled, so sorry for the misunderstanding. I imagine that there won't be an update for the firmware until after Windows 7 is officially released.