You don't have to load the game first. WHen you start Kawaks, don't load anything. Just click File -> Start Netplay and after you join a server, you can choose what game you want to play.
[Edit] Holy smokes! What is happening? When I bring up the netplay window, it closes in a blink, together with Kawaks itself :|
I see no logical explanation. I don't even try connecting to a server, it just shuts everything down before you know it. I've played online many times before and that's the first time I see anything like this happen. [/Edit]