The game is unplayable, first, the controls can't be remapped, this is annoying but not gam breaking. But second, when I move the mouse cursor, it simply pops back to the center of the screen, and if I click either mouse button, the game crashes. I already tried using Darkxl, but when I run, pointing to the Dark forces folder in GOGgalaxy/games, but nothing happens.

Some of the controls can be remapped if you run the setup.exe that should be in the games directory.