An automated download website

I need an automated download website for selling scripts, ebooks and templates. An example is similar to [login to view URL] I have found a suitable download script at [login to view URL] that provides function similar to the site. If there is no alternative, I would consider buying it and then start this project to modify its template. In case you have a better download script other than my choose one, please suggest it to me. I need a simple but attractive website and there is no need to have flash appear. A space should be provided for banner ad (I have a random rotated banner ad script and can be provided to you if required) Successful provider should provide: 1/ The script (in case you recommend a script other than my suggested one); 2/ A template; 3/ Installation of them to my server; and 4/ Integrate the payment system to my Paypal and 2CO account. 50% of payment will be given after the template/script will work on your hosting, the other 50% will be given after the template/script will work in ours hosting. Please specify if you just provide the template and installation work, and require me to buy the suggested script. If you have any questions or suggestions as to what you can do for me, please let me know. I have a small budget for the job, so please consider that as well.