Problem with downloads when paying with PAGUESEGURO

Problem with downloads!
Detail in Brazil we have a payment equal to Paypal , is the PAGUESEGURO, here comes the question if I have a downloadable product, like the way it is supposed to pay the customer has access to download it will have your product in hands before I THE OWNER OF SHOP has already received the money so that payments are falling into the account 14 days after approval, summarizing the client has the option to cancel the payment in case of not receiving the goods (but this and the case of products sent) but the client may use this flaw to make the product downloads and cancel the payment after he does the fake payment.
Question .. will download that would be more or less as in joomla (just an idea) the customer pays it and has access to a randomly generated code as a token with type settings. IN CASE OF downloads I can put restrictions on the type, token for download only works on a certain date or after a certain amount of days configured by store owner,
I know it sounds weird but good at preventing Brazil.
for example I had a client who did it, luck was that the product was of low value, but what if it was of high value? or product protected by copyright? as I have seen people here who sell courses, projects and other things. I think my idea should be taken in consideration and prepending more options as an option that I mentioned, including being more configurable and I think .. the virtuemart in joomla and more or less well and can be used only to get an idea of how it could be improved in OpenCart. thanks for understanding.