Continuity mistake: When Bond is beside the train going through the station there is nothing on the left, but as the train leaves a platform has appeared, and an engine shed and a brick bridge This was filmed back at the main station because of the double track set up.
Continuity mistake: When the train passes the signal box and the points get changed you can see the train in in the background and it is halfway past the station. When the Mercedes passes the train, it's still halfway past the station, and when the Mercedes catches it up again it's no further along. The train is moving at a constant speed the whole time.
Visible crew/equipment: When General Orloff first catches the train up, the reflection of the camara helicopter can be seen in the car's windows.
Revealing mistake: When Bond exits the carriage at the tunnel, it's an obvious stunt double.
Audio problem: When the circus train pulls out of the station just after Bond has the shoot out in the tunnel we hear the sound of a steam train pulling away with wheel slip, but the wheels are not slipping at all.
Continuity mistake: When the Mercedes is hit by the train head on, the car flies through the air boot first, and not turning. When it hits the water the car has turned around and is now engine first.
Continuity mistake: When Bond asks for the jet's tank to be filled, his cockpit swaps from closed to open between shots.
Revealing mistake: When Bond sends an assassin crashing into the tank containing the octopus, you can see the assassin is a dummy.
Other mistake: When Bond jumps onto the coupling of the horse-trailer, you can see that the idler wheel is already on the ground. It would be crazy to drive around a rough surface like near the racetrack with the idler wheel down - the trailer could be overturned. (00:04:50)