The Toolkit is the primary method to launching the Importer and for downloading/installing the Template.
OPTIM can be ran from any project using an Unreal Engine version specified from the installer.
Open up a new or existing Unreal Engine project
Click on the OPTIM button located in the upper toolbar.
If the OPTIM button cannot be found.
Open up the Engine Plugins window
Search for Optim under (Installed/Theia)
Check the enable button
Restart the Unreal Engine Editor
The Importer can be launched from the Toolkit's home tab.