Workflow tasks added to a change order are not saved when creating a template from a Change Order that has a Category assigned which has a list of workflow tasks defined. This technical document describes the scenario and explains that this is the current design for Service Management Service Desk.
Release: 17.3, 17.2, 17.1, 14.1
Workflow tasks added to change order cannot be carried to the new change order. Only the tasks associated with the category will be inserted, that is also happens because the new change order is created with that category. This is by design.
These steps outline how you can add workflow tasks to a change order template