Tyro screenwriters often miss the boat by not following the arcane inside rules: character arcs, jokes per page and beats. Just in time–Ross Mahler’s Script Beat calculator. The Mystery Man explains how it works:
You type the number of pages in your script and Mahler’s Calculator will give you a guide (within a typical 3-act structure) of the page numbers by which the various “beats” in your story should be taking place.
Blake Snyder also has a beat sheet download that helps WGA hopefuls with these labors.
FBLa wishes someone could invent a program that writes scripts for movies that adults want to see.