Quite a bit more info would be needed to help with this. Did you create routing interfaces on the L£ stack into each of the VLANs, under Switching > Configure > Routing & DHCP?
Given that Support are likley to have visibility of your Dashboard (for all this kind of stuff) - you might be better raising a case with them.
It seems you may have two possible paths to the Internet - one via the MX100, one via Velocloud device. How do you plan to use that? Dynamic resilience might be a particular challenge, I think...