Continuity: The last time Donovan hits Diana's craft with a laser, he hits it on the right side. But inside the craft it's the left hand side that explodes.

Continuity: When Diana is being chased by Donovan after crashing her craft, she has her normal human eyes. But during Donovan's strangulation attempt she has lizard eyes. As we saw in the original series, a Visitor's human eyes had to be removed by hand before the lizard eyes could be seen underneath.

Revealing: When Robert and Julie are attacked by snakes outside the cave, notice that in the shots when you see the backs of Robert and Julie there are hardly any snakes on the ground (I counted one) compared to other shots. The shots of Robert's leg as he sweeps the snakes away are almost certainly of a snake handler instead of the actor.

Revealing: When Donovan finds Diana's abandoned car in the desert, the outside shots of the chopper reveal that it is not Marc Singer at the controls.

Deliberate "mistake": When Robert and Julie find Elizabeth in the cave, there are all sorts of lights emanating in there, particularly a green one. Obviously done to enhance the moment, but most caves would be pitch black, and the cocoon itself was not generating any light.