There are several settings as highlighted below which user has to do while exporting the DGN to DWG file. But these settings are lost once the session is closed and user has to perform the same steps again for export. User wanted to save these settings somewhere so that they can save the time while exporting.
http://communities.bentley.com/products/plant/design___engineering/w/plant_design_and_engineering__wiki/24231.error-unable-to-open-seed-file-seed-dwg-while-exporting-model-to-dwg-format
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