I have a model that renders fine in Blender. I exported it to an .obj + .mtl and imported it into TG4. The .mtl didn't include map statements to reference the texture and opacity maps, so I tried to add those into the imported .obj file's internal node.
Most everything looks great, except for a glass sphere at either end of the model. It renders entirely white.
If I click Invert Opacity Image, the glass is entirely clear (absent from the render).
The image used for opacity has an alpha of 128 and RGB 254,254,254.
How can I get the glass to render, well, like glass?