From Degn's article: "... Some tests in XNA cannot be done dynamically. These tests usually require visual inspection and therefore need to be run manually. Using Testdriven.net you can run test scenarios, simply using an ad hoc test of a function containing the test. Simple. Effective. No need to modify the main method to run these functions.
However, when using any XNA content I have stumbled on the following error:
File not found. ---> System.IO.DirectoryNotFoundException:
Could not find a part of the path 'C:\WINDOWS\assembly\GAC_32\Microsoft.Xna.Framework\1.0.0.0__6d5c3888ef60e27d\Content\myTexture.xnb'
The reason being that (naturally) I didn’t put my content inside the GAC (Global Assembly Cache)! The ContentManager is using the codebase of the assembly who’s main method called it as its root ...".
BTW, in some chapter of Benny's book it's stated that this tool cannot be used with XNA GSE. Please notice that by the time the book was written, v2.5 beta -the build that reimplmented support for express editions- hadn't been released.
Cheers!