So, previously when I tried to import this ship, it would never appear, now I removed all the materials, found modifier "triangulate" and mapped some quick texture on it.
And this time it actually appeared.
I took it for a spin and I am absolutely sure I need to finish it, even if for BNG specs lowpoly would be better, this thing needs to be finished.
It looks like a murder machine on track and I even come up with unique gimmick so it will require special approach to handle.
Your post been a great help thanks Xpand, I am off to learning how to map a good texture.

One thing, I just started with Blender and 3D in general, "vertex normals" are like direction which shows which way mesh facing, right?
Shouldnt they be exported automatically like inherited quality of a mesh or I do need to do something to export them specifically?
Another thing, "vertex texture coordinates" are created when I unwrap UV map and place polygons on it, did I understood that right?