Rear shots of Frank's jeep show a man wearing a fedora in the passenger seat, but close-ups show Pepe in the passenger seat, wearing a sombrero.
When Doreen sees the Doctor's minions running around the forest, she's standing in front of the airplane. Her next few close-ups are in front of a black screen, even though in wide shots she has not moved from in front of the plane.
The pilot says his gyrocompass is guiding him in a different setting, probably due to a magnetic disturbance. Gyrocompasses are not affected by outside forces.
At several points in the dialogue, Dr. Aranya is said to be doing experiments involving "hexapods" - meaning six-legged insects. But he is actually working with tarantulas, which are spiders (not insects) and therefore have eight legs.
In various posters, actor Robert Knapp is shown, clothed, leaning over an also clothed Paula Hill, and, alternatively, shirtless over topless Tandra Quinn, with a jealous Paula looking on. In the film, Knapp's character has no relationship, indeed, no contact, with Quinn's.