Currently, we are working on the support of roles into the application. When finishing this task, the information about completed resources will be: user_id, role_id, role_instance_id, resource_id.
With this, before delivering a unit of learning, you must assing roles. Moreover, to reply an IMS-LD you will only have to re-instance a role, and the resources will appear as not-completed, and the imsld will be replied.
All this features are on development. We can call for test before commiting on CVS.