Emerald is one of the oldest Joomla membership extension with tons of features. Simple to manage but very flexible to configure for almost any subscription scenario. It has unique protection algorithm that can work with any extension without need of integration. But we made special fine tune K2 rule adapter to make it more pleasant to create restrictions.
Emerald integration contains 2 elements.
Action
Custom K2 action allows move user to/out K2 user group on success/expire subscription.
Rule
Rule fine tune adapter, allows:
1. Restrict access to article by categories
2. Set if article intro in category view is visible
3. Restrict comments by categories and hide comments form with replaced restriction text
4. Restrict attachment downloads and add lock icon to files to indicate protection