The big problem with this series and this movie in particular is that they have to stick with their own continuity. The vision for the movies is already set out, and the directors should have followed the books. They made glaring errors and unnecessary additions which throws off the series. My problems with this movie stems from the events at Christmas. That was completely wrong. In the movie's world Ron and Ginny are still happy and in school. I do not think they would be after those events. That was where they lost me. There were small annoyances like Greyback not being that important, no new Minister of Magic, no Bill and Fleur, and Harry did not "manage" the Marauder's Map (+more). This is not the movie for you if you love the books.