Problem with VRayMtlWrapper

[SreckoM]

Using night build for 18 Feb, I think.

Can not manage VRayMtlWrapper to produce correct alpha with shadows.

Checked mate surface, Alpha contribution -1, checked Alpha and Shadows. VrayMtl added to material slot, and Vray still do not render correct alpha with shadows. This was working before. Or I am missing crucial step ...