Crawford gets caught in a trap where he is tied up tight using razor-wire. You can see that his arms are tied close to his chest. When being carried off, though, his arms are away from the chest, loose.
When the bank truck is stumbled upon, Nate is asked how old the truck is and says that it was there since the 1950's. Later, when Crawford holds up some one-hundred dollar bills, you can see they are the modern style bills that were released starting in 1996.
When the bus is attacked by Three Finger you see barbed wire wrap around the front left wheel followed by the sound of a blow-out. A moment later when the bus is going off the road (in slow motion so it's very clear), you see that the wheel is perfectly fine.
When the prison bus's tire is popped by the wire from the truck, it starts swerving out of control. At one point the bus hits a railing on the side of the road but then it quickly switches to another scene, and there is no railing on the side of the road. Then the next scene the railing is back.
When Alex is hit by one of the prisoners, she falls back looking unconscious. However, several moments later Nate helps her to get up, and she does with no effort at all. If she was all right, why didn't she get up on herself earlier?
When the bus starts out, as Walter and Nate talk, you see through the front window that the bus approaches a right bend and passes an over-hanging tree on the left. About 30 seconds later, the same bend and tree are shown through the window.
When the police officers all meet in the station before trying to find the prisoners the chief states that there is 'a man' (implying Nate the officer) with the prisoners. There were two officers, Walter and Nate when the bus crashed. It isn't possible for the chief to know that Walter had already died as not even the sheriff knew. No one other than Nate and the prisoners saw Walter die so the chief stating there is only one man with the prisoners is incorrect.
The film is supposed to be set in West Virginia but the road center stripe is white. The USA hasn't used white center striping since the mid 70s, after the rules changed in 1972. Most of the legacy striping was changed between 1972 and 1975, and even the most remote roads were done by the late 1980s.