Thickness to scale means that you should use an object, like a flattened cube, instead of a pane that is one polygon thick. That is one of the most common problems with model for Poser/Studio, they don't have thikness. I generally hide the pane, if possible, and then add a cube that I scale to the right size. For the IOR just use the common glass preset.

What you want to obtain is based on the Fresnel effect and that is a consequence of light and camera angle. Just go to a window, move until you get the right effect and then take note of your angle in reference to the window. Using a digital camera is even better. Reproduce the angle with Studio's camera and lights and you will get the right effect.

Cheers. 

Paolo

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