I'd be interested to know how you changed the models?

When you open the project file I linked to, you can see what I have done if you open [font=courier new]Modify[/font] on your models:
All the [font=courier new]edge color [/font] instances have been set to [font=courier new]Invisible[/font]. Sketchup models are a bit messy and need to be cleaned.

My settings are quite universal, and will often render a nice image.
If you open [font=courier new]Modify 3D view[/font] , you will see that I have added a white solid texture to the sky.
When selecting [font=courier new]Enable sky lighting[/font] , you actually enable the sky to act as a source for image based lighting (IBL).
You could have a look at THIS THREAD if you want to read more about IBL.

You might also find some useful discussions and examples HERE.

Cecilia

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