Continuity mistake: After Mr. Palmer walks over and tries to pick up Claude Mulvihill's gun (which Jack kicks away) we see Jack's hat on his left. In the next shot as Jake picks it up it's now on his right. (01:19:40)
Continuity mistake: When Poirot and Mr. Ratchett first meet in the restaurant car, Poirot has to correct Ratchett's pronunciation of his name. Poirot then points with his right hand toward Ratchett, but when it cuts to a close-up of Poirot, both his hands are on the table. The angle changes back, and Poirot's hand is once again lifted.
Continuity mistake: And then there were four. During their tense conversation in the lobby, the Doctor gets close to Lombard, who has his jacket in hand. He holds the jacket in a different way (sideways vs more frontal) in the two different shots. (01:15:00)
Continuity mistake: Gene Hackman returns a second cookie to Harrison Ford's dish that he hadn't taken - or perhaps it's the same cookie he picked up and returned a moment earlier. Either way, the cookie had suddenly appeared in Hackman's hands going from one shot to another. (00:30:35)