Joomla extension module - Map link, choose city

Hi everyone, the project is basically creating a Joomla extension module. 1) when you enter the site, a transparent Grey splash covers the entire webpage. 2) then a small box appears, with 3 Tabs inside the box. 3) Each Tab has an XML maplink and below it a region selector. 4) At the botom of the box, there's going to be a GO button and a Cancel Button 5) On the right corner of each page, there's going to be a, CHANGE REGION Button, when clicked it will open the module above, and the user can then select an other region. I will provide the 3 XML Maps to lower the cost. To give you a picture of what I want, Its fusing both pictures that I attached and adding 3 tabs.