VS.NET 2005 isn't officially supported yet, although we are working on it. The problem is that Microsoft introduced the concept of Side-by-Side execution in regular DLLs (not just .NET), and that affects the way to correctly build the system.
I have an "unreleased" version of the make file that you can try if you are using LabVIEW 7 or 8. It isn't a VS.NET project, and I haven't tried it with the express edition, but I think it should work for you. What you need to do is back up your current <labview>\cintools\ntlvsb.mak file and drop in the one I've attached. Now just follow the documentation in "Creating a CIN", using a VC++ makefile (or using VC++ command line).
Let me know if you run into any trouble, because, as I said, this is a work in progress.