Quote - Of course you can simply turn off the sun light in Lux, without export/edit. I set the sky on its own light group exactly for this kind of tweaking...

You mean Sky? :) Yes, awf cuz I can, but even when you turn off a light (group) in Luxrender is still uses resources. It still gets rendered I think, since when I turn off a light group my S/P does not go up a single notch..