Deliberate mistake: The angle of the light coming from the film projector (which was up high on the back wall) was too high to actually project onto the screen across the room. Also, people were standing in front of the screen and should have been blocking part of the projection and have light on their backs but did not. The screen operated more like a DVD player on a TV. (00:35:20)
Deliberate mistake: Frequently during the movie, British surgeons are referred to as "Doctor". In Britain, surgeons are always referred to as "Mister"; this is a hold-over from the surgeon's non-medical past (barbers, etc). This would likely be confusing to American audiences.
Deliberate mistake: When they're watching the footage of the tsunami hitting Cannon Beach, Sabrina turns the TV off as the shot pulls backwards. Suddenly, the glare on the TV appears out of nowhere.
Deliberate mistake: When Nico finds Hilda's body at the start of the movie, her left arm is shown next to her body, and her right arm is outstretched. When her death is shown later in the movie, both arms are outstretched when she lands on the floor. (00:05:50 - 01:30:55)
Deliberate mistake: The movie is set in "Harburg County", Pennsylvania, but there is no county in Pennsylvania called "Harburg." (00:13:38)
Deliberate mistake: The agent is entering the office approaching his desk where a computer sits with the screen on depicting classified material. Computers left unattended go dark after x amount of time. This computer being in a federal FBI building should be logged out of and not open for everybody to see. (00:19:00)
Deliberate mistake: The surviving passengers are all awoken from a deep sleep after Dinah realises the other passengers have gone. Yet none of them appear drowsy or tired and none of their eyes appear strained, despite having just woken up so suddenly. (00:09:20)
Deliberate mistake: Gray's rental car just happens to be the one car out of the hundreds in the parking garage that the bad guy chasing Gray and Darby crashes into, setting off the bomb he had placed.