Hi,
The first thing you need to do is create a simple html page ( stand alone). This html page should have all the items you want on your modification. For example, if you are planning to have a form, place the form in this html page including the css. The next one, will be the form processor file, and finally test your script. For now, don't worry about the view.php. Modifying this will be easy later on, once you build a working prototype on what you want to make. The most important is to have a working stand alone script.
Once you are happy with the result, it is time we extend or modify the controller.php, view.php,add.php, edit.php and db.xml files. It should not be that hard, because it is written in OOP.
The main core of the comment block is the Controller.php. In the admin area, the settings are controlled by add.php and edit.php. The default setting options for the admin is delivered by the db.xml. Lastly, the view is where the form elements are located.