Restet Lion Server

OK, so I just bought the server app to play around a bit....I completely messed everything up as I had no idea what I was doing, so then I tried to uninstall it. I did this through various methods, and deleting files which I just learnt I shouldn't have deleted. Now the server app doesn't work at all. So I wanted to start again. I want to reset the server. I want to have that screen show that shows the very first time you launch the server app. How can I do that without having to do a clean install. Completely removing the server app (using appzapper) and putting it back on again doesn't help at all.

I would really appreciate your help.