Other mistake: After one of Col. Kirby's soldiers has been killed he takes the dead soldier's M-16 and smashes it against a tree. Instead of a magazine the rifle has a plastic sound box, because the 'rifle' is really a toy made by Mattel.
Other mistake: When Kirby and the Sarge are in the helicopter during the big battle scene, when Kirby talks to Kowalski, you can see that Kirby's mouth is not matching what he says. Look closely because his hand blocks his mouth.
Other mistake: When Peterson is walking and gets caught in the trap, when he flies and hits the sharp needle bed, you can see clearly that the right one of them bends like rubber.