1. Do you need to create nodes under the Test folder in treeview?
like
[-] Test
testpage1.aspx
testpage2.aspx
testpage3.aspx
2. Every node should have NavigateUrl set to testpage1.aspx (testpage2.aspx, and so on) ?
3. Any page in treeview uses the same master page containing treeview and
should maintain treeview state when you navigate to it ?
I can create a small example that implements this functionality for you.