(at around 24 mins) While they are making the video, the camera is moved from the tripod to the bedside cabinet. When they look at the tape the next day and see the door move, the camera is back on the tripod.
(at around 9 mins) The onscreen graphics shows that August 4th, 2012 is Night #1. The next one (at around 23 mins) shows that August 5th, 2012 is Night #4.