Continuity mistake: When Samantha is in the bathroom holding up two sample paint chips, in the first shot Sam is holding up the yellow in her left hand and the blue in her right hand, but in the next shot they've switched and are in the opposite hands, just as Jay arrives with the coffee.
Other mistake: When Tarkin walks out of the Batch's quarters and the shock troopers follow him, the one on the right side of the door has his hands positioned to hold a blaster, but no weapon is present. (00:38:35)