PAYPAL

Hi, I’m trying to set-up a paid download using PP as the payment method.PP API (API already set-up with PP)
Idea is, Buyer clicks on buy now. which take them tp PP, they by, and the file downloads to their desktop.
I have tried two plugins. ‘Easy PayPal’ & ‘PayPal Framework’ nether of which seem to work with API. or download.
Is there another plugin I could try?
Easy Paypal just kept telling me I had entered the wrong emil address or came back with a 404 error.
Paypal Framework I thought was to complected for my needs.

Thanks for reading.
Andy