Develop a Dynamic Download Manager

I need a developer to create a custom dynamic download manager for my file sharing site, filegag.com. To provide a clearer example, please follow this link to my site: [login to view URL] Navigate to the 3d final download page and download the file. I make non-premium users download a .exe file which is a dynamic download manager via another company. I want to create the exact same thing. If you have done something similar please share previous experience. Thanks.