Silverhawk170485: As already said:
Go to C:GOG games/Star Wars - Rouge Squadron 3D/ ROUGE and click on the ROGUE.EXE
Then a Startmenu opens instead of the game. There you can configure controls and set your XBox360 controler as default controler.
lemmer: Yeah, that doesn't actually work. It still isn't recognized in game.
I'm using a wireless 360 controller, and it would help if people specified whether they're using a wired or wireless one as they're technically two different devices.
I'm using a wired 360 controller.
I have no other controllers attached. The only problem as I can see it is my mouse and keyboard are also USB, like the controller. Not sure if that would effect it though, but it would explain why it's working for some and not others.
I'd use a mouse but it's so laggy it's impossible to play.