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It runs fine, but when I go to preferences and select the joystick, the pointer jumps all over the place. No matter what button, lever, triger, or stick movement I try, nothing stops it. Using Windows 10.
This question / problem has been solved by Strijkboutimage
Make sure the stick is the "preferred device" in the Windows gamecontroller panel, then go to the Red Baron installation folder and open Dosbox .conf with notepad and change:


Then you need to calibrate the joystick in the game, this can be done from the main menu or press Alt-C in the game.
I have the CDROM version and the thottle doesn't work very well in this, don't know about the GOG version.
AFAIK the joystick going haywire in the menu is a bug in Red Baron and should go away once you press a key or move the stick.