We have approval process on document.
Project manager insert document into Collaboration with specified type and there is process started for this type.
One step has manual action - Action item sent to resource entered in field on project page (approve/reject). This is correct and works fine.
Project manager can go to the Organizer/Action Items page. Here on list he can choose status Approved and save for this Action item which is assigned to different user.
When PM go to the detail of Action Item then its locked (RO) and gray but in list he can change status and save. On screenshots I am logged as Martin Paul