I can't access that URL while at work. ... if it's an image, can you use the attach feature of the forum?
"i thought when you went to v5.1 (we are on v5.10) that a vApp could encompass containing VMs from various sources ?"
Sources? Do you mean Elastic vDC? this is where an Organization vDC can Span multiple Resource Pools. This can happen as long as the network pool can span the backing clusters as well.
"What am i missing if my vApp is tied to the vDC, how do i have an application "group" which spans VMs from different storage locations ?"
when you access the properties of a VM inside a vApp, you can change the storage profile of the VM to a different profile. In this sense, you'll have at least two different storage profiles in use ... but just for different VMs.
Once the VM has relocated to the different storage profile, vCenter will perform the migration as required.