When Liza and John are in the basement of the hotel after the zombie shoot out, Liza says "We're under the hotel." and "What's happening? Why are we here?". On both occasions, her mouth doesn't move at all.
When the plumber "Joe" is in the basement, he starts to chisel out part of the wall right about forehead level. The next shot "Joe" is crawling into the large hole that he has made but has to duck really low to get through the space.
When Warbeck and MacColl enters the elevator at the hospital when they are escaping from the zombies Warbeck starts to reload his gun. Just before the elevator doors close we can clearly see that he put the bullets down the gun barrel as a joke and both him and MacColl starts to laugh.
In the credits, the character of Joe the Plumber is erroneously credited to actor Giovanni de Nava. Joe the Plumber was actually played by Tonino Pulci. Giovanni de Nava played the Zombie version of Schweick.