BUG Material assignment in Snapshots not saving

I am trying to save snapshots of different material applications to a model, so, one model with different materials applied that I can cycle through using different saved material applications in snapshots. I am saving the snapshots with the Material Assignment box checked in the snapshot dialogue box. I save different snapshots but if I close the file and reopen it all of the materials in the snapshots that were not visible when I saved it revert back to the default material. It is not saving the material assignment in the snapshot. It works in the same session of Rhino, but as soon as I close the file and reopen it all the materials are gone. I am using the latest version of Rhino and Vray 7.00.03