Changes to a WordPress Plugin - Server Side | PHP, MySql, Wordpress needed

General information for the website: Content Sharing Plugin for WordPress
Kind of development: Customization of existing website
Description of requirements/features: Hello,

We need help with some changes in http://wordpress.org/support/plugin/social-exchange-plugin WordPress Plugin.

We want to upload a PRO version to sell on CodeCanyon and we need to make a difference between Free and Pro users.

CURRENTLY this difference is made by manually changing two values in the database.

It works like this: an user installs the FREE version. When he pays for the PRO, we upgrade him by manually changing in the database:
-a text field, changed from "no" - "yes"
-a numeric field, changed from 25 to 500
When we change these values, all the PRO features are unlocked for that user.

WHAT WE NEED is a distinct version of the current plugin that makes these updates automatically (when plugin is installed).

I think some changes should be made on the server side also (otherwise anybody could modify the plugin and add points).

Please begin your proposal with "moresharesforyou" so we know you read this carefully.

We're looking for WordPress Plugin expert-coders. A good job will ensure future work.

Thank you for your time!
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