If you're writing a movie script and you want to protect that script as a copyright, should you send other documents along with it, or is the movie script more than enough? I am thinking whether other documents such as the worldbuilding manuscript and the overall plot should be included alongside the movie script.
If you just want to register your script, you don't need to send anything other than your script. Your script will not get more protection from additional documentation.
Also note that you generally have a copyright on things you write the moment you write them. Registering it just makes it easier to prove. I imagine publishing a signed hash of the manuscript could serve the same purpose.