Integrate Verotel with simple system to let user download 1 file after they have paida

I need an e-commerce web site that allows users to buy a mobile app (which is one 5MB file). Specifically: 1) I will provide the HTML for the front page of the site. It is a marketing page for the app and has a "buy now" button. 2) When the user clicks "buy now", the app then uses Verotel to do the credit card handling. You would need to set-up the Verotel integration. 3) Once Verotel has confirmed that the user has paid, I need a very simple system that allows the user to download the 5MB mobile app file. Once the user has paid, the user should be able to return to the system later, login again and download the app again. 4) However, the system will have some restrictions to prevent multiple users from sharing the same paid download. 4a) The user may login a maximum of 10 times. After the 10th login, the user may not login again. 4b) Each time the user logs in, the system gives them a download link that is valid for only one hour (and expires after one hour). 5) The system will be installed on a VPS, so you should be comfortable working in that environment. The mobile app is an adult (porn) app. You will not see any x-rated content while doing this job. If you would like to apply to do this gig, please let me know what relevant experience you have (especially if you have experience with Verotel).