The story is about a couple of ne'er do well Spanish guys who end up mistaken for Gods in the New World. The original structure had the heroes, Tulio and Miguel...trying to keep up the God act long enough to search the city for the fabled gold.The concept that if a story loses its forward movement the reader starts to get antsy I think is a good one. This doesn't automatically doom a story. Walter Jon Williams' "Incarnation Day," reprinted in Dozois's YBSF # 24, comes to a grinding halt several times to make way for massive infodump, but it is still a fascinating, can't-put-it-down story because of its characters, ideas, and worldbuilding; Swann's Way is still read, despite a somewhat, ah, liesurely pace. However, especially in a story that starts with action and ends with action, you need to think long and hard about the wisdom of killing that action even for a scene or two, because you risk losing your reader.
At some point, it got changed, and the directors and producers created the infamous Lay Low sequence. In this scene, the guys are simply given all the gold of the city, and the pair vow to 'lay low' for three days, waiting until a ship is built and they can leave.
I say infamous, because when we came back to the project, we tried (as did all) to fix the film, but that one story choice could not be overcome. The entire middle act of the film was designed to have the two lead characters actively doing nothing for three days. When you get to the Lay Low sequence, you can feel the movie come to a fish-flopping-on-dry-land halt, and then it just lies there with a glassy-eyed stare the rest of the way.
Here's a genuine writing tip: every scene you write should be a character in a situation. From page one on, you're only allowed to write scenes where the situations are clear, even as you go about revealing the main issue of your story.
The goal is to have a series of situations that escalate in importance, so the main story unfolds and builds, but only through filmic scenes that work on their own accord.
Lots of other good stuff in this essay, and on this site, too.