The best tip I can give you is this: they’re backdrops; they won’t carry a scene and they’re not supposed to be in focus. Also the included lights and ok at best if you want better you’ll have to loose them and add your own.
One issue I’ve found with these sets is that once you add UE2 to the mix the mesh tends to show up. To get rid of the “gridlines” sub divide the sky dome and hill geometry and you’re golden.
For a large outdoor scene they work pretty well but you’ll need have something good going on in the foreground.
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