php script for large files with unique link

Hi i am looking for a php script to download big files (up to 8GB) from a server of us. Something like this: [login to view URL] The above script does not require to my needs. In general i want to do the following: We upload a file to our server (outside the public html folder is prefered) We generate a unique link for one of our customer send the link through the script by mail with a short message and description and of course the link the user can download the file for a specified lifetime and only a numerous of clicks. The solution for us: We upload the files to FTP (outside public html prefered) start a php script (password protected, can be with folder protection) and select a file from a list (manually generated or automaticaly from all our files in a specified folder), set liefetime and as many times the link can be clicke. enter the email address of the client and click send. the script must be able to serve big files up to 8GB from one of our ISP. (We are not able to customize the php settings!) The links should be stored in a myswl database, so we can change lifetime and maxdownload if customer has a problem. If the user clicks the link the first time, the ip address should be stored in the databse, so the link can not be downloaded from another ip address. later, we would like to integrate paypal, so a customer can buy the software online and the link will be automatically sent to the customer if he paid. this is a addon feature in a second state. Thanks in advance for any bids. If you have further questions, pleae feel free to ask