I don't think you are getting the effect you are looking for realistically.  You are treating your cube as one piece of solid glass, like a paperweight.  If you intend to have a figure within a glass chamber, you will need to build a box from thin-scaled flat planes as walls.  That is fairly easy to do in Poser.  But if you want Scatter Volume within the chamber, then you will need the cube with separate material placed into the chamber.