I have had it all setup and working, when all of a sudden the playback of media will fail. Both on my remote machines and in the PLEX UI.
After some looking around, with several restarts of PLEX, Rock-On and the server itself, I found that going into plex settings, the mapped share I had added, as per the instructions, had dissapeared.
I never got an answer, and didn’t use Plex for some time due to this problem.
But since then I have reinstalled Rockstor and re-enabled Plex, and it now works without problems (except the Rock-ons not allways starting together with the system on reboot).