[dnanian]

It seems that the sleep problem might be the cause of your difficulty, though it's hard to be certain because I can't tell how you created (and updated) the backup.

What I'd suggest is to start the restore and then use something -- like a few AA batteries -- to hold down the Shift key. The keypresses should prevent sleep, and we can hope that that'll generate a good restore.

If not, doing an archive-and-install over the restoration should restore bootability...

Let me know if that helps!