Archonforest -- Sure, the .tgd is attached.
I did almost nothing but remove the shader that Hannes's .tgo object came with and replace it with the glass shader. Checked on the object's settings proper are: double-sided surface, visible to other rays, use smooth normals, cast shadows. On the glass shader itself, double-sided surface is checked. I changed no other glass shader settings from the default except to tint the "decay tint" setting a very light blue: strength is still set at 1.
To speed things up a little, I also turned the ray multiplier settings back down to .25 for the moment to see what would happen, and the "bubble" seems still to render just fine. There might be some slight loss of quality in the render, but I'm not overly fussed over that as there will shortly be other things going on "inside" the bubble that will obscure some of the view.
Hope this helps! -- DD
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