Hello,
I was trying out the demo version in max 2010 x64 with VRay 1.5sp4a. Whenever I drag out a new connection to any properties of a VrayMtl (vray material) I get a .NET exception. Seems to happen on any of the inputs but dragging a bezier float controller to the diffuse value is one concrete example.
I uploaded a couple of the callstacks though the exeption handler. Don't know if you have vray but there is a demo version available on the chaosgroup site.
Not a bug, but another problem is that the vray mtl ends up huge in the schematic view as all the inputs show up in one huge category. Not sure if there's anything you can do about that though.
Thanks
Simon