question about selling downloads, security issues etc

[Mary 2000]

Hi,
I have a few questions
Pleasek keep in mind I'm not a programmer..

I read that prestashop has a feature that lets you sell downloadable / digital items.
Before I learned about Prestashop I was thinking of using a service called Payloadz to sell downloads because
they let you store the items securely on their server, they collect the buyers info, so I wouldn't have to worry about hackers since the buyers info and downloadable items would be protected in Payload servers.

After I checked Prestashop I really like the cart, SEO features, it is really great.
But I can't find any module for Prestashop that would work with Payloadz or E-junkie.
I don't think anyone has developed yet a module that would integrate with these services.

Someone on the forum told me that Prestashop has an
in built feature that deals with digital items for download that I wouldn't need these services.

How about security? How does the delivery of the downloads work in Prestashop?
What a person could do to make your entire Prestashop safe agaisnt hackers , mysql injections?
Is there a database firewall type of thing, or buying a strong SSL certificate would protect against hackers?

I would love to use Prestashop, but I'm trying to figure what are the options to make
buyers info and files really safe

Any ideas?

Mary2000