Other mistake: Just before the evil robots capture Bill and Ted's girlfriends, after they crash through the window, the girlfriends ask the robots: "Who are you?" and Bill goes "Well, I'm really Evil Ted!" and unzips himself and out pops Evil Ted, and the other robot goes, "And I'm really Evil Bill!" and out pops Evil Bill. When the robots are herding the girlfriends out just before knocking them out with their breath, you can see two sets of clothes in the bottom left corner if you watch closely.
Other mistake: In the fight scene where Bohdi helps special agent Utah you see that his surf board gets broken in two and then after the fight he is seen leaving without the board, but in the scene where he and Tyler are woken up early to go surf right before Tyler says "you look like you just saw a ghost" you see him carrying the same board.
Other mistake: When the outlaws trap and rob a carriage in the forest, they put hooks on the back of it to keep it in place. But when the driver spurs the horses on faster, they run off, pulling the driver off the carriage and away behind them. There's no logical reason for this to happen, as you see the horses attached to the carriage, there is no evidence, either audio or visual, of the harnesses breaking, and in any event there really isn't enough force exerted for the harnesses to break to begin with.
Other mistake: During the fight scene in the TGRI building, when Michelangelo has the ooze and gets jumped for it and loses it, watch the bottom of the screen. Donatello is lying down and trying to get up. But in the next shot he's up and kicks out the ooze from the foot soldier. (00:26:35)
Other mistake: When the FBI agent says "Maybe it's time to get a real job" his partner can be seen mouthing the same words.
Other mistake: When the second group of people brought before the judge are sentenced, they are put to death in Mr. Bone Stripper. Curious note: though it kills the people, and chucks their remains out the end, there is absolutely no evidence of the clothing that was on their bodies. There is no pile of shredded cloth anywhere to be seen in the salvage yard.
Other mistake: When Leonardo lifts up the bar he has just fashioned, you can hear a couple of people in the background say "Gold" where the others are and correctly saying "Oro" (Since the Italian word for gold is Oro).
Other mistake: As Peter stands on top of the rocks, you can see a distinct difference between his appearance and Never-land. Also, as the camera pulls back to follow his progress through the Lost Boys area, a vine is seen shaking on the left side because the camera hit it.