(at around 21 mins) When Bob Lawrence and his daughter exit the chalet porch to watch the trap shoot, Bob pushes the left door outwards. When the camera cuts to an outside view of their leaving the building, it's the other door that is swinging shut, and it is closing from the inside.
Near the end,Peter Lorre is seen firing a German 7.62mm Mauser automatic pistol out the window and hitting a policeman holding a .303 Enfield rifle...seconds later,still at the window,he is shown holding a British Webley revolver.
During the shoot-out when Peter Lorre goes over and stands by the window, the pane closest to his right shoulder is broken; only half of it remains. The shot cuts away and then back, and now the pane is intact.
In the scene where the man is shot through the window, near the beginning of the film, just before he is shot, he turns to face another man. At that time, you can see the beginnings of a blood stain on his shirt next to his lapel...before he's shot!
The goof item below may give away important plot points.
Abbott's suicide is rather unconvincingly portrayed: the puff of smoke that emerges from the side of the door, in accordance with the angle at which he is holding his Mauser C96 when the door is pulled back, along with the fast timing of the scene, makes it seem at best extremely unlikely that the gun could have been pointed at his chest (where his hand is clutched) at the time the shot was heard.