Add the Edit... (context menu option) to the Records tab in the Change Order List.
Or have the Add... and Remove buttons enabled by Default and inform the user on educate rights upon using the buttons.
For info:
Many users struggle to know when they are able to edit a Change Order, it also does not help that the Add... and Remove button options are greyed out.
Either remove these or have them working properly, I do understand it can be useful not to reserve the Change Order when a User has it selected and an additional action is required for this.
