Hallo. i have edited my post putting a smaller and so easyere to download file.
Im very new to lightning. Ive created a scene but want lighting with atmospheric lightning and have ligthning from a plane behind my scene plus ive added a sun in the hope ill get shadows. But no shadows. What am i doing wrong. is it the atmosphere lights or the plane? . Im not sure. Have i missed a setting in the sun lamp? or is it just way to many lights?
my blend file: http://www.pasteall.org/blend/42588