1) The demo featured the Sub bar during the minato boss fight with 4 Subs like in Generations ( Each subs is represented by a log. on the bar ).
2 ) Minato gets one move when he's awakened, L1 & R1 each with a different cooldown.
Press one of them and Minato trows a Kunai, if its connects he rasengan his opponent from above like in the manga.
3 ) Awakening is INSTANT. You heared me right. Awakening is instant. ( Press R3 to use Awakening. )
4 ) Awakening is not longer linked to your chakra bar, you can awaken regardless of your chakra bar when you're low life.
5 ) And last you don't get full chakra bar when Awakening is available. Yep you read that right.
From there we can guess two things.
Everyone gets L1 & R1 new moves when Awakened.
Or it just a story mode thing.