want to add php script pages for more secure PayPal transactions

Permalink
Hi,
I'm new to C5 and not a developer, though OK with basic code editing.

I want to add a PayPal "Buy Now" button to my site, and I want it to be more secure than the default html code that PayPal provides. I plan to sell only a single physical product and later a digital download, so I don't want to pay for the eCommerce add-on. I was going to use this add-on:
http://www.concrete5.org/marketplace/addons/paypal-digital-delivery...

but it apparently has problems; the developer says don't buy it now, and I wrote but did not get a response.

So, what I want to do is along the lines of what is recommended here, where a set of scripts are provided (as a free download):
http://www.squidoo.com/paypal-button-security...

The php pages provided are to be uploaded to my site, but I can't figure out to integrate this into my C5 site. Is this possible? How do I do it? I'd appreciate some help, thanks.