The mammoth task of making a single-threaded UI getting multi-threaded

At the moment I’m working on a single-threaded WinForm UI that will have to consume WCF Services over the Internet. The problem of such a change is, that the UI is getting really languorous due to the service response times. That’s why I’m going to rewrite it for multi-threading. At this blog-post I want to describe the problems I have to face, and the way I solved it.