Select this when you want to use a template (a MicroStation seed file) for the exported DGN file. Then click 
(Browse) to navigate to and load the template. Vasari exports the project to a DGN file using the settings in the specified template.
If you do not use a DGN template file, Vasari exports the project to a DGN file using default settings.
Note: You can select Enable DGN Template File when exporting to DGN only. This option is not available when exporting to DWG, DXF, or SAT.