Hi Stan,
We have Joomla 3.3.6 and VM 3.0.2 with your last versión (2.7.5).
In a test server or an real, we have problems. In both sites, we can not complete a order. When you go to checkout to complete order, always return to cart page.
You can see in this sites:
www.relatosalacarta.com/test2/
www.cuidadicos.es/test
One site have a copy of real site and the other is a new and clean installation without plugins.
Thanks!!