Continuity: Cathy's muff disappears when she turns around after entering the room.
Continuity: As Cathy walks uphill to see Heathcliff, her entire costume changes.
Continuity: Near the end of the deathbed scene, Cathy has her arms around Heathcliff's neck, and takes them away. When the camera angle changes, her arms are around his neck again.
Revealing mistakes: In Cathy and Heathcliff's romantic scenes on the moors, and in the open window as Cathy is dying, the wind is blowing powerfully, yet the background clouds never move or change shape.
Anachronisms: Though the social situations, and even the soundtrack, are consistent with the novel's timeframe of 1770-1801, the Colonial/Napoleonic era, the costumes are clearly an odd mix of mid-Victorian and American Civil War.