I found two problems with the management of the package associated with a workflow :
If you add a document in the package and you press directly the action button to go to the next step of the workflow, this document won't appear in the screen of the next task. To obtain an effective insertion of this document in the package, you have first to press the button "Save Change" and secondly you could press the button to go to the next step.
If you specify (by configuration of the custom model associated to a task) that the user can only add some documents in the package, he won't have the possibility to remove from the package the document he just added. Then if the user select a wrong document, he should leave the task (clicking the "cancel" button), re-open the task and retry.
