Other mistake: They go to Texarkana, Texas, to pick up the beer, and later in the movie, they are in Fayetteville, Arkansas. Why would they go due north to Fayetteville to get to Atlanta, which is East?
Other mistake: In the end credits, Christopher Walken's name is listed as 'Christopher Wlaken'.
Other mistake: When Mel Brooks is singing the song "High Anxiety" to a bunch of people in the dining room, near the end of the song he sings about two words and his mouth is clearly not moving. (01:00:10)
Other mistake: When some of the team is visiting Lupus, there is a picture given to Lupus of him catching a long fly ball in his glove from the first movie. However, the picture taken was up close and there is no way a picture that close could have been taken as nobody with a camera was anywhere around him on the field when the catch was made. In addition, nobody expected him to catch it, so the close up picture is not possible in reality.
Other mistake: When Mrs Slocombe is having her passport picture taken the images taken are not directly in front of them where the actual photo camera is, rather they are taken from the camera filming off to the side.