HELP! Rhino 6 model won't open in Rhino 5!

Aaaand, I need to transfer my model to Rhino 5 so that I can use V-Ray, and possibly T-Splines…

I’m beginning to regret my decision to test out the newer version of Rhinoceros. Is there any workaround to this?

Have you tried Save As to Rhino 5 format?