your aspect ratio looks fucked and the game is way too dark
I don't know how bright it is supposed to be. The values are set at the default. I'm running the game on EDuke32 for what it's worth.
Cassar How do you run the game?
If you're using the Polymer renderer, the game might be a bit darker due to the different lighting model, but there are some fairly dark areas in the second episode. As for the aspect ratio, try the toggleable widescreen option in the in-game settings; it corrects the aspect ratio when using a non-4:3 resolution, if I recall correctly.
One thing about resolution in DN3D. I haven't tested it in EDuke32 recently, but in the original version of the game at least one feature isn't rendered correctly in resolutions above 320x200, the kind of green acid or goo the Enforcers can throw at you, which appears as droplets flowing down the screen. They're large and multiple, covering much of the screen in 320x200, but at higher resolutions they often don't appear at all, or just one or two are visible. You can test it by starting the third episode, inputting the god-mode code (
dncornholio), and waiting for the Enforcer that gets up to the roof to perform the attack.
Anyway, if it's the first time you're playing it, I'd suggest going with the original version in DOSBox. Those earlier shooters just aren't the same without the background demo recordings in the menu, which source ports can't play because of desynchronization due to changes made to the code.
There's also a reason at least to stick to the software renderer, as the skyboxes don't look right either in the Polymost or Polymer renderer (though it's worth noting that the former was created by the engine's author, Ken Silverman). Besides, true three-dimensional rendering isn't that good for games with sprites either as it causes the latter to feel less like part of the world with actual volume.