problem solved... Michalis was so kind to explain to maybe.
I was a bit wrong about OBJ not supporting uv maps.

I'll explain the workflow quickly here for people who are intrested:

unwrap your object in Modo. make an texture in gimp/photoshop. apply it in modo. export to OBJ. import in blender. export as 3ds in a different folder with the texture in the same map. Remember 3ds files can only contain 3-5 letters. import into SU

thnx Dylan.... it's still a WIP so I'll post some new renders when I'm done.
I already undid the smoothing. I'll experiment with the roof when I got some free time.

It's an indoor swimming pool water.. I tried fog with different multipliers but I hardly see any difference. For pool I don't need fog? and I don't need a volume either for a good water effect?
thnx for the reply and also on asgvis website.