Yes, Visual Studio 2013 Community Edition is supported.
No, the former Express editions of Visual Studio don't support add-ins (they have
no Add-In Manager). Microsoft did not consider them to be used professionally
(they are intended for students, hobbyists, etc.) and removed support for
add-ins. However, the new Visual Studio 2013 Community Edition does support add-ins.
Any problem not addressed here? Don't hesitate to ask.