Given that I have a shell application and a couple of separate module projects using Microsoft CompoisteWPF (Prism v2)...
On receiving a command, a module creates a
That all seems like a lot of work!
Personally, I just declare a resource dictionary in my view's UserControl.Resources section like this...
UserControl.Resources
That merged dictionary then points to any resources I need to include.
You'd declare your data templates in there I guess.
HTH.