Digital Art Zone

How do I make all of the windows in GIS Orion transparent, or better yet, have the refraction of plain glass? I want at minimum, the lighting effect shown in the product page. Ultimately I would like to light it from the outside. But, so far, it is acting like the whole thing is opaque with no light coming in from the outside.

Have you tried playing around with the Opacity slider?  Try some number lower than 100, maybe closer to 25-50.  0 is completely transparency.