In the HOW TO: Create control designer for user control post I have very nicely explained everything, except that I have zipped completely wrong files. I am really sorry for that and apologize to anyone who ran into problems and frustration with that code sample.
On the bright side, it took me just about a month to figure that out and post this fixed code sample. :)
Here is the sample code for that post that actually works. The instructions and explanations are same as in the previous post.