I think you could greatly enhance the appearance of this mod with two solutions
Split the tower and the crane into two sprites
-The tower can stay in the background of whatever's below it
-The crane is in the foreground like the rest of the sprite is now. (According to the big screenshot on the main page for the mod)

You'll probably be using some image editor software to do this, so while you're at it, I think a little color alteration pass might be good? Like, just tweak the hue and saturation a little to bring it closer to the vanilla feel, but that's just like, my opinion, man. I'd be willing to assist on either or both just to sharpen/keep sharp my image editing skills.

My friend, whatever you want,

If you want to work with bitmaps, they're included in the package...

or

I also have models in FBX and ready-made scenes in Blender.

The next step is to animate the model, which means you'll need to cut the single model into independent elements.

TBH, everything I'm doing with GIMP at the moment is just an attempt to procrastinate at getting good with blender.

Well, it's probably a waste of time to play around with Gimp now, since I'm planning further modifications to this 3Dmodel and new renderings anyway.