I just tried the new Iray+ 1.2 version and there seems to be a problem with some glass pieces rendering black.

I am using the standard Revit model house, linking the Revit file, converting it to Iray+ and rendering. Some of the glass pieces render in pure black while other render normally.

Black Glass.jpgGlass House.jpgGlass Isolated.jpg

Detaching the individual Glass elements from the Editable Mesh modifier seems to somewhat solve the problem, but direct light still does not pass through the glass!

Semi-Fixed.jpg

Here is the same render with the left glass panes hidden.

Hidden Glass.jpg