It isn't related to You *ekhm* problem report - point 2 and 3 was mentioned so many times in this thread, that I'm going to leave pleasure of finding it to You. IF device is unbootable after restore, either: 1) You've did something during backup process, that made backup corrupted, and you've ignored warnings, by restoring such existent, but wrong backup
2) You're trying to restore rootfs+optfs backup made with some custom kernel, on device with stock kernel
3) Everything is ok, and You're just booting it up with keyboard open. To be honest, personally, I bid for the 3th.