Updating your copy of Final Draft 9 will NOT affect your scripts, which are saved separately on your hard drive. You do not need to deactivate Final Draft 9 before updating.
Update steps are different depending on which version of Final Draft you currently have installed. To see which version you have, open Final Draft and go to Help > Get Help (9.0.6 and later) or Help > Customer Support (9.0.5 and earlier).
If you have Final Draft 9.0.4 or later installed:
If you have 9.0.3 or earlier installed, you must download the installer, available HERE, and follow the instructions below.
7 / Vista: