In the library when Ms. Bonnard is trying to find Mike & Amy, the camera operator (in an orange tshirt) can be seen clearly reflected in the glass of a picture frame on the wall at the back of the library.
After Amy realizes her mother has turned into a zombie, Mike says, "Your mother is dead." Amy replies, "Alive." Mike says, "Same difference." The line doesn't make sense this way. Amy should have said, "Undead."