Continuity: Right after Clementine removes the piece of glass from Lucas' leg, there are repeated shots of the bedroom door as the intruders try to get in. During one such shot the handle that had just busted off reappears, intact. In the next shot of the door the handle is once again missing.
Factual errors: When Clémentine finds her car in the woods and she gets in, she is frantically looking for her keys but she cannot find them. But you can clearly hear and see the windshield wipers moving.
Crew or equipment visible: When Clementine drives to the house a crew member (most likely cameraman) is visible on the car glass.