Other mistake: Lakella seems to disappear from the movie after the battle.
Other mistake: The subtitles of the international version translate a few things completely wrong, including, when the body of the warden is found, "There were three men!" instead of "It happened at half past three." (00:04:25)
Continuity mistake: Marty is in a school shower stall facing outwards. It is a close shot. He is dry and completely naked. He covers his genitals with his right hand. A large swath of the top of his dark pubic hair is plainly visible. In the next shot, as he exits the shower and moves to his right, he is still completely naked, however, he appears to be covered in thick soap suds from above his belly button all the way down to the lower part of his thighs to the point that his pubic hair is not even distinctly visible. (00:05:50)
Visible crew/equipment: In the opening sequence, Sammo Kam-Bo Hung is scavenging the dead soldiers (with one hilarious twist) - however, when he is holding the ring, in his sunglasses you can see several very much alive crewmembers standing. (00:02:45)
Continuity mistake: When everyone is having dinner and one woman is on the end of the table then it shows her at a different end of the table.
Continuity mistake: After the car accident, a man in a black hat and coat runs up to the left-side rear window of Patton's car, taps on the glass, then peers into the car. The camera angle changes to show the Jeep arriving and we see the same man in black arrive again to repeat all the same moves exactly. (01:13:30)
Continuity mistake: The drunk biker holds his can of beer low in one scene, then closer to his mouth in the next immediate shot as he asks about Lance's bike.
Factual error: The movie as the opening captions say, is set in Melbourne, Australia, 1978. However when Sam at the beginning of the movie drinks the milk and moves to the other room where the TV is, he passes by a poster (a communist party poster, the Italian communist party, strangely enough) that was designed only in 1981. (00:09:25)
Revealing mistake: When Louise pulls off Joel's trousers, we see that he is wearing briefs under his boxers.
Continuity mistake: When the van crashes into the stage at the marathon, the crash happens in two separate takes, as you can see by the position of the guy in a light blue jacket, who dodges the incoming vehicle with radically different timing in the two shots. (00:03:20)
Continuity mistake: Torok the Troll wears a magic silver ring which allows him to appear in the form of Wendy Potter. However after Wendy's mother tells her about the orange juice, when Wendy touches the cold bottle of milk in the fridge she grabs her arm in pain and we can see both of her hands, and she's not wearing that magic ring.
Revealing mistake: The soldiers pour gallons of nerve gas to knock a humongous gorilla down, but none of the guys not wearing a mask are affected the slightest bit.
Continuity mistake: Liana is barefoot most of the movie yet at the chief's village she's shown wearing black ankle socks.