I am not sure if you guys know Aaron Stebner. Aaron works at Microsoft, and has pulled thorns from my side many many times already. His blog is at http://blogs.msdn.com/b/astebner and it is a gold mine of tips and tricks to debug and solve many cryptic issues happening during installation and removal of programs. For example, Aaron taught me how to remove programs that do not appear in the Programs and Features list, amongst many other things.
The last nugget I used from Aaron’s blog saved my butt just before a presentation where I had to run both Visual Studio 10 with the Windows Phone SDK, and Visual Studio 11 for WinRT development. Of course this had to be on Windows 8. Unfortunately when you install the Windows Phone SDK on Windows 8, you may (or may not, I saw both scenarios) encounter an issue with XNA, and the installation fails. Unfortunately, even if you don’t use XNA in your apps, this will prevent even normal Windows Phone app development. Fortunately, Aaron has a fix for that.
I hope that this helps spread the word, and increase Aaron’s blog’s visibility!