This is essentially a dupe of this thread. The stderr logs are red herrings. The font message can be fixed by running:
launchctl load -w /System/Library/LaunchAgents/com.apple.fontd.useragent.plist
The ClientCallsAuxiliary error can be fixed by running plex as root. Resolving these issues however doesn’t make the plex server work. It just hangs. This is a bug in PMS.
