Layer Management > Shade Down (Manage Menu)

This command can be used to shade down layers by identifying objects that are assigned to the desired layers. To shade down a layer means to set the attribute "Shade Down", i.e. the layer will be displayed in a gray color.

Choose the objects whose assigned layers are to be altered. Click on objects to choose them, including objects in locked layers.

After identifying the objects, their layer assignment is determined and all affected layers are shaded down.