When PMS 1.1.3 was announced, it came with a new security scheme:
- When PMS is logged in to plex.tv, all clients need to be logged in as well. There is however the possibility to authorize some IP’s so that they can access PMS without being logged into plex.tv
- When PMS is not logged in to plex.tv the Plex clients can access it locally, but not remotely
Discovering servers through GDM and/or DLNA requires multicast to be active in the router. Multicast does not work accross the WAN port (maybe it can cross it if that port is bridged with LAN ports, but I can’t test this). Multicast does not work accross VLAN’s by design. And probably will not work through VPN.
PMS servers can be discovered using GDM/DLNA but their libraries will show up empty unless you authorize the IP’s as stated in the PMS 1.1.3 announcement. Did you authorize the IP’s during your tests ? It is necessary to authorize the IP of the device running PlexConnect plus all ATV’s.
If you use PMS versions older than 1.5.1 you are on your own. See this announcement. Several Plex clients (PlexWeb, Roku, etc) will refuse to work with older servers. Remote access (through plex.tv) will not be allowed. Probably the metadata collectors will not work also.
In summary, it is highly recommended to use a recent PMS version and have the ATV’s signed-in if the Plex servers are also signed-in. Regarding GDM, I can modify the timeout value if necessary.