For SteamWorks, you need to download the SM extension (not just the client libraries, which is what you have). Go to this page and choose the most recent build for your OS:
http://users.alliedmods.net/~kyles/builds/SteamWorks/
Extract the files into your addons folder and restart the server. Please note that you'll need the sockets extension for SM as well.
To change the password and other settings for the Chat Relay plugin, edit the cfg\sourcemod\CheckValve.ChatRelay.cfg file.
Hope this helps!