having trouble learning Mental Ray
 

I am trying to teach myself mental ray, and I decided I would do interior scenes and gradually move from very basic scenes to more complex ones as I learned the intracicies of mr. I already have a few questions, and I was hoping some of you could help.

#1: I am starting off doing an increadibly simple room (basically just a box), and have a light source entering through a window. I hoped GI would even out the light distrivution, but unfortunately I still get very stron concentrations of light. An example of this problem is attached. how do I fix this?

#2 I really want to get the "white window" effect whereby it appears that a window is illuminated by sun and is too bright to see. An example of this is in drubster's excellent interior lighting study-notice how his window seems to glow just a bit
study: http://forum.simplymaya.com/showthre...threadid=14402

#3 What do the mental ray materials, such as Dgs_material do, and how do I apply them-is it just like regular shaders, or is there something special? I have a very limited understanding of this.

Thank you very much for your help