Continuity mistake: At breakfast, the morning after Maria has just arrived at her Uncle's house, the uncle calls Maria's father a coward. He has a glass of brown drink in his hand. He's just taken a drink and the glass is 3/4 full. Maria angrily refutes that her father was a hero and the glass, still in his hand, is now full to the brim. (00:19:20)
Continuity mistake: In the scene where Daphne is talking to the peasant farmer after leaving the King, Luster casts "Flaming Hand of Fiery Doom". Daphne blinks a few times and has a shocked look on her face, but has no other indications that a person exploded in front of her. In the next shot, Luster comes up and pulls "a piece of peasant" off Daphne's cheek that wasn't there before.
Continuity mistake: When Despereaux fights the cat in the rat arena, he hides behind a blue ball of yarn. When the cat hits the yarn, causing Despereaux and the yarn to fly in the air, in the next shot, the ball of yarn vanishes and never reappears again.
Continuity mistake: When Adam and the puppies are racing just before they reach the first checkpoint, there is a wide shot and you can see that Rosebud is on Shasta's right side, but when we go to the close-up, Rosebud is on the left side, but when we're in the close-up just after Adam says "Great, no one's limping", Rosebud goes back to being on Shasta's right side.