Using "Import from iTunes" in Advanced Premium music library options? Premium Library with iTunes

Can someone please provide detailed information on the use of iTunes with the Plex Media Server? Within the support help articles for setting up the Plex Media Server is a section under the Premium Plex music library titled “Import from iTunes” which states “This option requires that iTunes be installed in the default location on the computer running Plex Media Server”. I do not understand what that statement means. My configuration consists of a Western Digital My Cloud EX2 Ultra NAS running the Plex Media Server and a Mac computer running the iTunes. The WD Sync utility is configured to keep the iTunes music media residing on the Mac synchronized with a mirrored copy of those files locally stored on the WD running the Plex Media Server. The iTunes is installed on the Mac in the default location for music: \Music\iTunes\iTunes Media\Music. I have created a duplicate directory structure on the WD and configured WD Sync to update the \Music\iTunes\iTunes Media\Music folder and its subfolders with any changes made on the Mac. When creating the Premium Plex music library, I selected the \Music\iTunes\iTunes Media\Music folder on the WD within Add folders.

I have an extensive iTunes library on the Mac with approximately 3800 albums with 48,000 tracks. I have spent a considerable amount of time creating the library and adding accurate metadata, so that the library is very well organized. I utilize playlists extensively as well within the library to further enhance its organization and tailor it to my needs and liking.

I plan to continue to use iTunes on the Mac, but add the Plex Media Server running on the WD for the added features and functionality it has to offer. I would also like to utilize the iTunes playlists I have created in my Premium music library. How would you suggest I create the Premium music library to provide the best experience based on my wants, needs, and current configuration? Any suggestions you might have for improvements to my configuration/setup would be most welcome, such as files or whole directories I may also want to keep in sync. If you could step me through any options I may want to select or unselect during the creation of the Premium library would be fantastic as some of them are not real clear on what their function is or how to set them up are.

Thank you very much for providing assistance with this project!!!

Plex Media Server: 1032461. Mac OS X: 10.11.6 (El Capitan). iTunes 12.4.2.4