When Little Hal's machine makes the Sheriff a cup of coffee, the machine spills milk and sugar all over the cup's saucer. In the next shot, as the sheriff picks it up, the saucer is completely clean.
As Duane Bradley tries to climb from the bus window the bus's lower rear-view mirror is missing, then, after the bus arrives at Uncle Hal's house, the mirror is now in place.
In the ending credits, "Animatronic Technicians" is misspelled as "Anamitronic".
As the bus drives away from the drug store, the film crew is reflected in the bus windows, most notably, the sound man holding the boom pole.
When the grandmother is collecting items from the shelves in the convenience store, as the camera pans along, it is reflected in the mirrors in between each shelf.
When the Sheriff walks up onto Uncle Hal's porch you can see a tape marker on the porch floor, on which he later places the item which he is holding.