Factual error: The movie is set in the late 1950s, yet Ed's car has yellow-on-black California license plates that weren't issued until 1963. The plates on Ed's car should be black-on-yellow 1956 issue plates.
Factual error: Ed Wood films Lugosi exiting his house, and grabbing a flower near the entrance, a scene to be shown in "Plan 9". However, in fact, the real scene of "Plan 9" shows Lugosi exiting his house, walking across a garage door (that doesn't exist in "Ed Wood") and grabbing a flower around there.
Chosen answer: According to Tim Burton in an interview at the time, they were "taking a little vacation from each other", - he also said that he was not sure what the situation between them was, which certainly implied a falling out. Danny Elfman is a bit more open, describing what happened as "a family feud" - he says that after working on six films together in ten years, they had a bit of a creative fallout, which led to Howard Shore doing the music for Ed Wood. Afterwards, according to Elfman, they realised that they missed working together and went back to collaborating happily.
Tailkinker ★