Continuity mistake: When Richie is telling the other 3 guys to go to the corner, he still has his hands on the wheels of his chair. But when the shot changes and Richie says "if you need the toilet then put your hand up", his arms are crossed around his waist.
Continuity mistake: When Richie falls off the ladder, it's apparent from the way he falls that he lands on his front (you just see his leg pop into shot) and that his head would be pointing towards the camera. However, instantly in the next shot we see him on his back with his head towards the wall.
Revealing mistake: When they are leading Richie to the cupboard while playing postman's knock, Dave Hedgehog puts his hands on the wall. The whole stage wall shakes when he touches it.
