Try cranking this this value in your directional light: I have been messing around with these values on the height fog too: Mainly the distance and falloff, fog density etc so I could get a nice few rays only close up, with the shadowy end of the corridor Looking good!
Looking good, some critique:I would try and make the fabric look more like its going underneath the mechanism/solid parts and try and get the pinching effect, adding more creases etc, then you'd get the look of the fabric being looser but pulled tight at the seams. It perhaps looks a little too flat right now, though I see…