The template you downloaded (script.dot) contains script styles and hidden styles. Script styles are the ones you would expect to use in the script: dialog, character, etc.
Sample script showing some script styles from script.dot.
Hidden styles are extras that you can use for keeping notes. They are called hidden because when the hidden text option in MSWORD is checked, they cause the tagged paragraph to appear. When the hidden text option is unchecked the paragraphs tagged with a hidden style tag disappear from the screen and from the printed script. They are always there. You just hide and unhide them as you wish (just don't forget to hide them before printing the final copy for submission). script.dot contains two hidden styles: Notes and Question.
Standard script showing the hidden styles from script.dot.
Download style template script.dot