VSTO Changes / VS Release

I'm preparing my machine to be our demo machine at the Visual Studio launch event on Monday.

One of the very effective demos that we've done in the past involves Digipede-enabling some .NET code behind a spreadsheet in Excel. It drastically reduces the time it takes to run, and only takes about 20 lines of code to do it. Really, really cool stuff.

So I installed VS 2005 on my machine, only to learn that VSTO isn't part of it. So I downloaded the 400MB VSTO install and installed it. It's a little strange, because it seems to be its own installation (not just an "add on" to Visual Studio).

However, now when I try to open an office project, I get a message telling me that I need to install Microsoft Office Professional Edition 2003 SP 1. This is a problem, because I have Office Professional Edition 2003 installed already! I have SP 2, though, not SP 1. In any case, I can't actually create or open an Office project.

Has anyone else seen this problem?