When you launch the Writer application, you will see your list of scripts. Slide one to the right and you'll see three icons (Delete, Rename, Duplicate).
These commands will enable you to keep your script list current and accurate.
To start a new script, touch the plus sign at the upper left and choose the template you want.
To create a test or alternate copy of a script, duplicate it and rename it.
NOTE: Final Draft 9 has a much larger selection of script types and templates to choose from.