Revealing mistake: Just before Charlie is stabbed you can see the "blood pack" under his shirt.
Revealing mistake: While driving the Mercedes to the house of grandma, the gauges on the dashboard show speed is zero and the engine is cold.
Revealing mistake: Whenever the astronauts are outside the module they are affected by being in a lower gravity environment. However, when inside there seems to be no effect, an example is when the helmet falls.
Revealing mistake: When Carter puts the dead guy in front of the thing that blows your tires, right before he runs over him, the dead guy blinks his eyes.
Suggested correction: The blinking is too obvious to be a mistake by the actor, the scene is supposed to show that the man was still alive after being stabbed, as a final bit of suffering. Terribly unrealistic in real life, but not for this franchise.
Revealing mistake: When the cannibal throws Porter's body on the table you can plainly see its a rubber body. Especially when he cuts off the head.
Revealing mistake: As the guy is being pinned down by the giant hooks you can see for over a minute he can simply escape and slip his hands out. (00:52:30 - 00:53:30)