The liberties taken during the movie I feel do not change the story much if any in the ways continuity. Some of the segways taken bring the novel into a motion picture in that long or diatribe dialogue was condensed into a few seconds of action. The characters were developed more so than in the past. The film also captured the horrors of love and loss among the students. The themes are becoming more adult as the children progress through the series, e.g. puberty, sexuality, love, heart-break, and the case of Harry and Ginny, seemingly forbidden love. The movie was made for everyone regardless if you read the novels or not; and J.K. Rowling approves each movie.