Overlay File Format
The overlay file is always a V8 DGN file, regardless of whether the reviewed file is a V7 DGN, V8 DGN, or DWG. Overlay file names must have the overlay.dgn extension.
The overlay file is always a V8 DGN file, regardless of whether the reviewed file is a V7 DGN, V8 DGN, or DWG. Overlay file names must have the overlay.dgn extension.