Previously all application level resources in a project I am authoring were stored in App.xaml. Then i decided to migrate from VS 2008 to 2010 and that is where the trouble started.
After migrating, I tried to do a little testing using a testing window instead of the normal startup window. After changing the startup object, suddenly I was faced with lots of compile errors and what not which (long story short) resulted in finding that there was now two files which held application level resources associated with the project: App.xaml (the original), and Application.xaml (at this time veritably empty). I migrated all of the resources (as well as merged dictionaries) over to the Application.xaml, and all was again right with the world so far as Visual Studio was concerned.
I then found out that Blend still wanted to use the App.xaml. I had created several resources and placed them in the Application.xaml, and saw that they were not being used when I compiled with Blend (but they were being used when i compiled with VS).
Where does one specify which xaml is the top level WPF resource file? This is getting out of hand...
Cory