If you installed the Navisworks Exporters during the install, follow instruction in the Navis exporter docs and try out the NWCOUT command. By habit I export to a seperate folder than where my dwg is kept. This was due to some issues in the past when the BIM coordinator is working with and updating their NWF files from my live files. It may not be an issue any more though.
You could also look at your Navisworks export settings with NWOPT command. If your using the Navisworks Freedom viewer, you may need to use the NWDOUT command in ASD due to the Freedom limitations. I believe it only opens NWD files.