I reference "object" and "shader" respectively.
In that time, I selected some faces and assigned at those.
After then, I changed "referenced shader" (remove a shader, so lose assignment)
To fix change, I reassign another shader to object but I can't do that.
There is warning like that.
## Warning: Cannot add "polySurface1" to "lambert2SG" because they are in a missing set within a referenced scene. Reload the referenced scene if it's unloaded, clean up the referenced scene or remove corresponding reference edits if the node has been deleted in the referenced scene. //
It seems that the case is caused if I assign to faces not whole object.
How can I resolve the problem?
The only way to do is to do not assign to face?