On the Isle of Portland in Dorset it is consider very bad luck to say the word "rabbit". As a result, when the film was advertised there, the local poster changed the wording in the title to The Curse of the Were-Bunny.

Source: Mark Steel's in Town: Series 1, Episode 6 - Portland

Nick Park wanted to call the film The Great Vegetable Plot but audience research in the US advised that the word "vegetable" had a significant negative rating amongst children.