Newkirk and Richter enter the cooler cell through a moving block in the wall. In other episodes, the cell is entered through a door in the floor under the sink.
When the Field Marshal and Gretchen arrive at the Stalag, she is introduced as Fraulein. This is inappropriate as she is wearing a military uniform and therefore should be addressed by rank. Also inappropriate is her appearance at the dinner table in civilian dress; she should be in uniform as are the three men.
The car that Richter arrives in has the steering wheel on the right. German cars have their steering wheel on the left.
Hochstetter's collar insignia (a single spray of oak leaves) is that of an SS-Standartenführer (equivalent to the army rank of colonel). However, his shoulder insignia (a plain strip of silver braid) is that of an SS-Sturmbannführer (equivalent to the army rank of major, which is how he is referred to throughout the series). A Standartenführer's shoulder strap should display two pips.
When Richter's car blows up, the explosion comes from the ground, not the trunk - where Hogan planted the explosive.
When Klink proposes a toast to Hitler and the Field Marshal and the Corporal turn around to toast the picture of Hitler, Schultz takes a big gulp of Cognac and when the shot shifts back to the three Germans, the bottle of Cognac is on the table. Not enough time for Sgt. Schultz to put it there.