Not sure what's going on. I can't seem to get any volume or glass effect on the "Wine" part of the with Wine Glass. Even if I attach the same glass shader as the glass, no volume effect is applied. Just black. Surface reflection seems to be the only thing effected.
Shadows for the object are off.
Nested transparencies are not working properly yet. If you have a model where the wine is completely inside the inside surface of the glass it should work (i.e. an air gap between glass and wine). You'd just need to increase the max ray depth. Lots of objects (including this one) are modeled with some overlap (no air gap) because that works better in lots of renderers. Terragen 4.4.44 needs the air gap. I'll get this working better in future versions.
In my glass of wine experiment I took out the inside mesh part that was the wine and saved as separate part, so the real glass was a single sheet, only touching at the very edges.
Thanks guys good advise, and hope that endeavor doesn't give you too much trouble, Matt.