Visible crew/equipment: After the main characters have entered the mall through the skylight, and have gone down the stairway in order to secure the mall, Scott Reineger and Ken Foree open the door into the corridor leading to the control room and boiler room. Whilst walking through said doorway, there is movement in the shadows in the top left. This has to be a crew member, as the only other zombie that is in this area is in the boiler room.
Factual error: When they are refuelling the helicopter (as a zombie approaches quietly from behind) the actor has put the gas nozzle not into the hole for the gas tank, but into one of the foot-holes that helicopter mechanics use to climb up to the top of the helicopter to do repairs. It doesn't even fit properly.
Continuity mistake: After parking the first truck in front of the mall doors, Roger jumps out and runs towards Peter's truck. Notice the zombie wearing the red and black striped rugby shirt. After Roger runs past him, he breaks zombie character and becomes concerned about his shirt being tucked in.
Continuity mistake: Near the end, Steven is in an elevator, and the zombie opens the doors and starts biting him. When he gets them all out of the elevator, blood comes out of his mouth and down the right side of his face. But later the elevator doors open and Steven is a zombie and the blood is on the left side of his face.
Revealing mistake: When Peter (and Stephen) are locking all the doors, Roger gets his rifle from the back of the car and shoots a zombie. Even though the bullet goes into the side (two-inches away from the middle of the zombie's head) a small amount of blood shoots out the middle, and something at the edge breaks off/moves, revealing that it's a tomato sauce sachet stuck to the actor's head.