Thanks for your email. The Library Paths section of the preferences should be used to point to the parent directory that contains libraries. I see from your screenshot that you are only pointing it at the maps folder.
Instead, you should add the maps directories to the Customise Project Paths > External Files menu as shown below
Forest Pack actually should take care of this for you, it scans the library locations for folders called Maps and adds them to this section automatically. I can see you have this enabled in your screenshot so I am unsure of what's happening. As a first step I would check the External Files preferences to see if the maps folders are already present.