When Mary leave's her apartment in England to chase the Saint she packs one suitcase. Later when she arrives at Dorfeld and asks the porter where to find a taxi, she has a suitcase and hatbox.
The railway engine shown in the train journey carrying the Saint, his friends and the bad guys is a different engine to that which eventually pulls into the station en route from where they all alight.
The Saint handcuffs the injured man by the wrist to the bed post. When the Saint discovers the man has been stabbed, he is no longer handcuffed to the bed post.
As Simon Templar attempts to escape in Rudolph's car, Rudolph pulls a switch to close a gate. Up to then Rudolph and his assistant have been bare headed but as they run after Simon they have hats on.