Click on "reply" on a thread and you'll get the register button.
Scratched my head over that one for a few minutes...
I saw it this weekend I'm having a bit of a problem.... I connected my Edge account to the wrong Live ID All my other Microsoft logons (TechNET, XBOXLive, etc) are connected to my old-skool account. Do you know if there's a way to change this?
That bug has since been fixed. We had a bug that if a user wasn't signed in and they selected Reply it would redirect them to a "forms based" authentication screen instead of Live ID.
This should now be fixed.