The add-in has been developed in 3 stages ranging in complexity from drag-and-drop to writing code that uses the Reflector SDK. After the download Reflector should appear in a tool window. The first time the Reflector Add-In loads it will prompt you to download Reflector. Go to the 'Tools/Managed Add-Ins.' menu and select Reflector Add-In.
That's all you will have to do! The new version includes the Reflector Add-In (make sure you uninstall any old versions first). Install the latest version of ManagedAddIns.msi.
If you're impatient and just want to see the Reflector add-in running - here's how you do it. I wanted to start developing it using VS.NET 2003 whilst maintaining compatability with 2002. I have been developing it using VS.NET 2002 but it has worked on both 20 for a while. I started writing the ManagedAddIns framework when NUnitAddIn (a unit testing add-in project I have been working on) started becoming unmanagable. It will be done using the ManagedAddIns framework. NET Reflector can be made into an Add-In for Visual Studio.NET. This article will show you how Lutz Roeder's.