My live disconnected right before I got the achievement "Awakening" and now it's not counting towards my gamerscore. Any idea why and how to fix?

Recover your gamertag.

This achievement hasn't counted for me either and my Live never went down.

You have to delete your gamertag off your xbox, then download it again. I had to do this because I was in the beta and Microsoft Online did not recognize the achievements until recently, so even though I earned 8/10 achievements before the content was released, I have to re-earn them.