Any volunteers?
Alright, version 1.11.123 works, but there were no multiplayer games at all when I tried that out, so either the Network configuration or whatever was changed in any version between now and the current, or nobody at all was online, which I would assume is unlikely.
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If nobody's on Descent 2 games often after all, would someone be willing to set a time and date to test out multiplayer on my machine? I'm willing to bet it won't work, but it's always worth a try.
Oh, wait, hang on. This version always gets hung up at where it shows the different enemy types in the mission briefing. I'm gonna give an older version a try.
Version 1.5.172 will get past where version 1.11.123 will, but when it attempts to launch the game, it says something about there being a wrong polygon pattern or something, and fails to get to the game itself.