See:
http://decentfilms.com/reviews/kingdomofheaven.html
And good review. I never doubted there was anti-Catholic sentiment in there, just that the trebuchet scene was good. For some people in this world, that may be the only glimpse they have of anything religious. If they even start to look into the Crusades after following that movie, isnt there a possibility of conversion ? Don't want to sound like an ecuмenical modernist, but sometimes I see (very rarely!) that conversion can occur through means (books, movies, etc) that seem uncharitable to the Faith upon deep analysis by those already of the Faith.
For instance, someone sees some exorcist movie, they never knew of the word "exorcism". They look it up, and are just amazed by the Catholic Church and their battle against a supposed invisible army of evil out to get their soul. They pray one day, and convert after seeing the goodness of God and receiving grace to believe... AKA that was my conversion, in one way.