I started to watch this and like most of these kinds of films, started to find it strangely compelling. What drew me in was the photogaphs. But then I did some googling and found this site:

http://www.clavius.org

It has step-by-step debunking of the various theories. I haven't read them all, but did check out some of the examples about shadows which appear to go in different directions. This site might be a useful companion to act as a counterweight while watching the film?