Remote Access, Cannot connect outside home network

Hi All
I have done something to my Plex Server running on a WD PR2100 server. I cannot get Remote Access running correctly. I have enabled Remote Access but “Not Available to Outside Network” stays in the red. I have tried to manually specify public port (32400) but this doesn’t help. I am running plex through the PR2100 server with my google router system. I am trying to get through the help pages but some of them are a little complicated for me especially when it comes to working with the router setup. Any ideas would be much appreciated. Thanks in advance Rob B.