Other mistake: When the two Americans are walking on the moors, their shadows are always in front of them, despite them having changed direction numerous times. Additionally, with the moon always being behind them, how are their faces being lit?
Other mistake: Dennis Quaid is supposed to be frozen in a wall of ice but if you watch closely, and very quickly, you can see him blink his eyes.
Other mistake: Towards the beginning of the film JJ (Burt Reynolds) lands his plane in a town to get more beer. You can clearly see the a large crowd of spectators in the background standing behind the wooden barriers which the police had set up for the filming.
Other mistake: When Arthur is in the bath tub, Hobson brings him a martini on a tray. Arthur grabs the glass. It shoots over to Hobson then back to Arthur and he picks up the glass again without even putting it down.
Other mistake: There's no way Harry could've smashed the cigarette vending machine at the gas station without somebody inside seeing him.
Other mistake: Towards the end when Janet, Brad, Oliver and Betty are singing "We're going to do it anyhow," as they are dancing down the aisle, Betty very visibly trips and grabs Oliver to stop from falling over.
Other mistake: For corpses which have spent around a decade lying in water, the zombies' hair and uniforms are surprisingly well-groomed.
Other mistake: In the private conversation scene with Bill Murray and "Sarge" in the latrine at basic (Sarge's office) the toilet bowl in the back left corner is installed backwards. (00:43:03 - 00:45:10)
Other mistake: As Debbie walks through the foggy maze from her upstairs bedroom to the bathroom across the hall, she closes the door and then asks herself why she is in the kitchen, when the kitchen is obviously downstairs.
Other mistake: After Leonardo sets up his canvas to begin painting The Last Supper with Jesus with his disciples, he says "hold it" and then the camera flips to show the men (and Comicus) now situated behind the table. Look at the disciple in the blue tunic at the right, who first looks off to his right, then corrects his position, and faces left, with his arms extended. (00:52:32)
Other mistake: After Earl and Vic tangle in the swamp, Earl staggers back to his house to discreetly use the basement shower, where he is shocked to find Vic already there and waiting for him, hiding in the dark behind the shower curtain. Both men are literally covered from head to toe in thick, muddy muck from the swamp. but there is no trace of mud (handprints, smears, etc) on the shower curtain nor in the clean, white shower; and, when Earl manages to chase Vic out of the basement, he leans heavily on the door for a moment after slamming it, which should have left a huge, muddy print on the door's clean, white surface. But, as Earl steps away, there is no muddy print on the door at all. (00:38:57 - 00:39:42)