Quiz phpFox Customization

The quiz phpFox has some limitations, so the need to improve it. My goal is to create several wanted to be able to sell access to my users, but will not prevent my users can also create free quiz the way it is available in phpFox. I need the administrator is able to add categories to quiz packages to sell, and questions with feedback. Phofox Quiz: [login to view URL] Ideally quiz, the administrator can create quiz with feedback, you can create categories, create packages to sell and many other things. In phpFox, the quiz is created so that any user can create quiz, however, the system is simpels, for example, does not organize the quiz categories, have character limits on questions and answers, does not allow the same user to respond wanted more than once .... I need to enable the administrator to phpFox to create quiz with feedback, create categories and packages to sell. Hello, I need to exemplify, see the attached picture. Note that you must add: category option, increasing characters withdraw limit only once in response to the quiz; feedback to the question. Recalling that these changes should be enabled only for the quiz created by the administrator. See image attached