Hi Norton,
I am in the same position as yourself trying to create multiple vlan environment within a single VApp. After researching for 2 weeks, I was almost ready to give up but am glad I found your post. I was trying to achieve the same with Clavister and it didn't work with the VLANs setup on the Clavister. It seems like you didn't create any VLAN using Vyatta? Is that correct or did you create VLANs on Yyatta?
>>>ensure that the Vyatta has a connection to each of the networks
What do you mean by the above? Did you have to add NIC for each network on Yyatta?