I use Discovery Launchpad V1.2 and have tried putting -s discogc.game-host.org:2302 in the additional parameters line as well as trying the numerical IP addresses and it doesn't work.
I've also tried adding -s discogc.game-host.org:2302 to the command line of my shortcut, but it still goes to the main menu.
Is there any way to edit an .ini file or something to make this work?