My co-worker is using VS 2010 and has tried to upgrade her solution from SL 4 to SL 5. After figuring out a couple of compiler issues because she had some old assemblies, at runtime, when the "new DeploymentCatalog" is executed, an exception is raised that wasn't raised in SL 4.
Here is the error message, but is there any reason it shouldn't be able to work in SL 5?