In the book a large battle between Aurors, teachers, and students accurs in the school against the death eaters. The only explanation I could think of to cut out such action is budget for special effects which angers me because it is what really makes the end of the book so exciting to read. The death eaters just walk out the school without any trouble. On top of this I wonder why Harrys meetings with dumbledore didnt get the full attention as the book where dumbledore suggests why and what the other 7 horcruxes are or could be through other memories.