The War Control chatroom is an IRC channel which can be reached by clicking on the ingame War Control link which will open an IRC client webinterface.
However you can also reach it without the webclient. To do this you need to use a standalone IRC client (e.g. chatzilla, xchat, mIRC, pidgin, ...) and issue the following commands:
/server cpugod.synchro.net
/join #testing
The channel is protected against hostile take over, and most of the time there is a channel operator who can - if need be - kick or even ban people from the channel. Should cpugod.synchro.net not react quickly enough, you can try
/server irc.synchro.net
as a backup.
For those of you who are unfamiliar wirh IRC, wikipedia offers an general (technical) article If you want an standalone IRC client, I recomment ChatZilla, but there are many other. Here is a comparative list
For those who are using a standalone IRC client, here is a short list of useful IRC commands:
/server irc.synchro.net   The server command will connect you to a specific server network, such as the synchro.net network, or dalnet (irc.dal.net), ircnet (irc,ircnet.com), efnet (irc.efnet.org) or undernet (irc.under.net). The last 4 are known as the big 4.
/disconnect     This command will disconnect you from the network
/nick nickname  This command allows you to set or change your nickname - mostly restricted to 8 or 16 characters, space is disallowed.
/join #channel   This allows to join a channel (aka chatroom). To join our channel, use  /join #testing
/part   or /part #channel    leave a channel
/away reason   mark yourself as temporarily unavailable (the reason is optional). To come back use the /away command with nothing else (some clients will recognize the /back command to come out of the away status)
 There are more commands and possibilities, some are incoorporated in IRC clients. You can find a full list of IRC commands on wikipedia. Some servers offer specific services such as nickname protection (NickServ) and channel protection (ChanServ). Some networks allow IRC bots, others don't. When in doubt check the website of the network.
