Hi,
I ran into this same problem today as well. Did a lot of searching, and found this thread.
Strange that I'm able to use an EntityCollection as the datasource for a RepositoryItemLookUpEdit (a combo box type control that can be used within DevExpress' WinForms XtraGrid for looking up FKs to display some other attribute like a name from the foreign table) but it didn't work with a TypedView.
I tried it with and without a BindingSource and the result was the same - with the TypedView, the lookup didn't succeed and the field was blank. With an EntityCollection, it was OK.
The failure was silent as far as I can tell, so not sure what further information to provide.