[Question] Payment Processor/Giveaway with FB Share and Tweet

Hai there,
Firstly sorry for my bad english.

Does anyone know any good "payment processor" or free give-away
platform where user need to choose either share the news in FB or
Tweet the promo before they can get the free product?

Something like Opt-in concept but viral using social media.
But a platform which is more secure instead of redirect to an open page.

I know one which is http://cloudflood.com/ but it seems that it is
not secure because once the user share/tweet it will direct to the
download page for example w3.mysite.com/download and they
can share the direct link to their friends in the future and by-pass
the share and tweet.

Does anyone know any similar platform that can provide a much secure
service or anyone have any other idea on how to prevent this?

Thanks in advance for your help and advice.

Cheers

You can use a random link generator so that one link will work only once and then use cloudflood, you are done.
Enjoy !!

twitter.followers said:

You can use a random link generator so that one link will work only once and then use cloudflood, you are done.
Enjoy !!

Click to expand...

In the cloudflood there is only one place for me to put 'direct link to freebies'. Is there an option to create a random link generator there? unless there is a step where i miss out...

Thanks