Crowdfunding Script Modifications

Hello, we are [login to view URL], in France We are looking for a developer that can modify our Script Guru Crowdfunding [login to view URL] in this way: Actually the script make that is users can do donations to open fundrising projects. Money donated go directly to admin Paypal account and then admin ll send to project creator the money raised. We need to modify it in order that if the project is complete and the amount is ok admin can pay the project owner as usual sending the full sum by paypal: for exemple target was 4000$ in 10 days and all donations were 4000 $ , admin can take 5 % and give the rest to the project owner sending by paypal. ->BUT If the target of donation is not reached in the time scheduled project owner can can a) extend the time line of the project or b) he can close it and money ll be refunded all the people that donate on this project . This means that it cannot be done as actually script works because paypal cannot make possibile pledges. But we need that the Payment gateway get the transaction without bill the donator and that it bill him only in 2 cases: target reached in the deadline setted by the project creatot. We think it's possibile integrating the script with Amazon payment gateway.