Other mistake: When Arnold and Gerald first bump into Helga at the bus stop, they ask her for bus money, but throughout the rest of the movie they never need bus money.
Other mistake: While Arnold and Gerald are headed to FTI on the city bus, Murray tells them about Mona. When Murray says, "You meet a girl, you think it's forever," the animation is a bit skewed, as it shows the steering column going through Murray's right thigh. (00:46:25)
Other mistake: After Murray and Mona are reunited, when Arnold and Helga talk about the crazy day and the really nutty things that were said, we can see stores on the block behind Arnold, but the animators have misplaced Mr. Green's butcher shop; it's not where it should be. Then, when Helga agrees that she hates stupid football head, Green's Meats is next door to Art's Shoe Repair, right where it should be. (01:10:00)
Other mistake: In the FTI records room, when Arnold and Gerald open safe deposit box 999, the box is quite empty with a mirrored surface, and we can see the reflection of Scheck appearing behind them. The problem is Scheck's reflection is not backwards. (00:50:50)
Other mistake: When Bob and Nick start fighting, Nick runs into the kitchen and grabs an egg beater. Right before he tries to attack Bob with it, his right shoulder is drawn incorrectly. (00:49:32)
Other mistake: When Arnold says that he needs a VCR to show the tape, and the camera moves over to Bridget, her appearance is way off: the yellow and gray pieces are missing from her belt, her collar piece is missing, her boots are just dark brown instead of light brown and dark brown, the lines on her suit are not drawn in, and the VCR and zip line device are not in her hands. All this stuff appears in the following shots. (01:07:05)
Other mistake: When Helga kisses Arnold on top of the FTI building, Arnold's hat falls off his head, but you can see another hat on his head as the other one is falling. (00:58:02)
Other mistake: When Bridget tells Arnold and Gerald, "If you're gonna try and save the neighbourhood, you're gonna need some equipment," Arnold's right eye duplicates. (00:35:55)
