Reviews List and sends reminder to person assigned a task 7 days before due date, and every day until task has been completed.
This Site Workflow queries a List called KPI and looks for 5 main fields. It will calculate 7 days before Task is due and if an action is required of a person. If so, it will send reminder to complete task 7 days before its due. If still not actioned upon, reminder will still be sent until status is completed.
Nintex Workflow 2013
SharePoint Server 2013
This is a Site Workflow. In the email notification, there is a link to the item in the list which will require you to configure so that it points to the right URL