A small CMS for subscription-based website

I own the website http://www.metoxesxaa.gr/winner/ which is a subscription-based website (the fourth menu button from left reads 'Subscribe').

In essense, what I want to do is substitute the graphics of that website with new ones.  That's all!  That website has a completed CMS 'under' it, which we will use as it is.  The new subscriber of the new website will see what the new subscriber of http://www.metoxesxaa.gr/winner/ sees, and me (the Admin) will manage the subscribers of the new website the same way like I do with http://www.metoxesxaa.gr/winner/ (of course a new mySQL database will have to be created for the new website and 'linked' to it).

Lastly when you click at the 'more' of the editorial in http://www.metoxesxaa.gr/winner/ you will see an overlay appearing with text.  In the Admin I have the option to upload that text, the corresponds to the Editorial/more button.  In the new website a few additional buttons like that 'Editorial/more' button, where I will be able to upload different texts (different .html's, to be more proecise) for each one from within the Admin.  That's the only difference of the new website with the 'old' website http://www.metoxesxaa.gr/winner/.  That's the only thing you will probably have to program (the .php code of http://www.metoxesxaa.gr/winner/ and its Admin is, nevertheless, at your disposal, if you want it).

Please see the attached folder that contains brief further explanations in 'Explanation.doc', a sample .html of the ones I wish to upload to our new website and three very informative screenshots.