How can I create addons for Live Messenger 2011?

Question

If I want to develop an addon for WLM 2011, where should I start?

In the past we could make add-ins using .NET, but it has been dropped or at least I can't activate.

How does Messenger Plus! Live modify the Windows Live Messenger? How can I develop an application like that? Where may I find documentation for it?

Answer 1

I believe that the documentation you are asking for is here.