I'm having a problem with a Bill of Materials in trying to set a sub-assembly as a phantom level so that the drawing Items List shows the sub parts. In the image of a BoM, the last item, 15194T BODY, is set as 'normal'. If I change the setting to 'phantom', as soon as I click away from it, the setting changes back to 'normal'. Does anyone know why? The only thing I've noticed is a symbol by the part number saying it is 'promoted' but I don't know what this means. The BoM level must have been set to phantom at some point in the past as I have a PDF copy of the top level drawing with all of the sub parts showing.