Rendering turns black when I link mechanical model

[scott746257]

I am working on some interior renderings for a client. My rendered lighting works with no linked file as I have my light fixtures hosted in my arch model for this exercise. When I link the mechanical model in, the rendering produced is a pure black box. Do I need to adjust settings in the mechanical model prior to linking? The mechanical model was created with a nested arch model as well See screen shots and thanks for the help!!!