Sync Subasm Props buttons missing

Using NX12/1953: I have set model geometry in the master model to certain layers and colors. In the drawing file, I want to sync those master model properties, which I have done a million times. I always right click on the subassembly (master model) select properties. In the dialog box under Assembly tab, I select Mixed layer option, and then one at a time select each button at the bottom (Layers, Display, Attributes.)
In this instance, which I have never seen before, the three buttons at the bottom are missing in the box altogether. As far as I can tell, I have done nothing different. Has anyone encountered this before?

Curtis