Load the scene and run IR in the viewport.
Drag the rightmost texture tag from the object "panzer oben" called "Metal - Gold.add" down in the object manager so it becomes the rightmost tag of the object "rock".
The object "panzer oben"becomes transparent in the viewport IR.
Restart the IR, thing go to normal.
Now reload the file, run the IR and deactive the SDS.
The drag&drop operation and the render results are as expected.