I've volunteered for so many things...I'm in the process of making a "Modman MegaPack" and I'm also in the process of creating two factions, so I don't have the time for a tutorial. But I can tell you that all you need to do for the XML is to make sure that the files referenced by the XML actually exist, and that the files you are looking for are those that it references. The best I can tell you right now is trial and error, I guess.