At the beginning of the film, Susan closes the blind in the bathroom with Webb standing outside. She does not close it all the way, leaving a couple of inches of the glass exposed at the bottom through which you can still see Webb's badge. But, in the next shot from outside, the blind is completely closed.
When Webb is climbing up the hill, trying to run away from the police near the very end, at one point he slips downward, which would have been the end of him; after a quick cut it's as though he never slipped (where he would have fallen), and is right back to climbing arduously again.
When Webb drives out of the ghost town to chase after the doctor, the image is flipped. This may have been done to use previously shot footage but keep screen movement consistent going to and from the ghost town i.e. arriving from right to left and departing from left to right. This manipulation is revealed, and a continuity error created, because Webb is seen from the exterior shot sitting on the right side (of a left-hand drive car) as it drives past, but he is sitting on the correct left side in the very next shot taken from inside the car in the back seat.
Webb's new Cadillac has California plates, but he lives in Nevada.
Webb tells Susan the birth of their baby will increase the ghost town's population by 33-1/3%. The birth will increase the population by 50% because the population will go from two to three.