The live server view page gets its data via the Server Queries (http://developer.valvesoftware.com/wiki/Server_Queries) and a simple A2S_INFO (http://developer.valvesoftware.com/wiki/Server_Queries#A2S_INFO) call.

Currently it does not use the rcon feature and therefore no more data is available, since the implentation is not working right now.

The error message about not getting the data and the server is unavailable, can be caused by multiple things:

Server is offline
Server crash
Game not fully loaded
Server not ready
IP or Port is wrong (no data will be recoded , too)
Socket timeout ( a gamesever should have a quick response time, so increasing it will not really solve the Problem )
If you start the server with -insecure, -nomaster or both it will also not work ( don't ask my why...)
Currently there is no direct link between the players shown and the players already recorded. Therefor the click on the player name will result in a player search in this game for this playername.
Perhaps I will/can extend this with a direct link to the player profile.