Revealing mistakes: As Koukol places the lid onto Herbert's coffin, the edge of one of his "ugly hand" rubber gloves becomes visible.
Revealing mistakes: When the three escape from the dance, they come across bats hanging from the ceiling and the Professor starts studying them. When Alfred pulls him, the Professor stumbles across rocks on the ground which are obviously much lighter than real rocks would be.
Continuity: When the Professor is trapped in the window in the crypt, both he and his spectacles move between shots.
Revealing mistakes: When the Professor first enters Count von Krolock's library, he puts his spectacles on at the tip of his nose, so that he can read some of the books' titles. He nevertheless looks right above his glasses, thus making no use of them.
Continuity: Abronsius and Alfred attempt to enter Count Von Krolock's crypt through an entrance on the ground floor, the crypt itself being located in the cellar. However, when apprehended by Koukol the Hunchback, they decide to go for a window entrance instead. To do this they scale the castle wall and enter a top floor window, with the crypt itself magically relocated to the top floor.
Continuity: When the Professor and Alfred attempt to enter the underground crypt of Count Von Krolock, footsteps in the snow appear and disappear.
Continuity: In the GB version, at 52:56 there's a daylight view of sky and mountains with no trees through the castle window as the hunch-back/vampires assistant lays down the coffin. At 53.20, after a cut, but still in real time, the view from the same window is now a night-time one and appears to be somewhat different with higher mountains, trees and no sky.