Question. When creating a process instance using the engine, it seems that the task is auto created through the engine but the due date is not properly getting set. Is there something else that needs to be passed in or done to get the due date correctly set?
search for examples in the activiti source jUnit tests. In the case when it does not help try to reproduce the issue in the jUnit test https://forums.activiti.org/content/sticky-how-write-unit-test. In fact there is nothing specific needed to set due date.