Just to sum up. There are 2 ways to "export" to DWG one is to do a "Save As" (Individually) from the View and the other is to Publish (Multiple Sheets). Also there are 2 items that we can "Export" and those are "Views" (Individual Drawings) or "Layouts" (Sheets with Multiple Views).
In this case I would try to do a simple "Save As…" to DWG and choose any of the predefined Translators to see what mistake you get, post the screenshot so we can help troubleshoot. If that works ok then try a Publish (using a predefined Translator) and take a screenshot of the mistake.
eduardo rolón AIA NCARB Another of the forum moderators. Macbook Pro 2.4 i9 32GB ram OS X 10.XX latest AC25 US/INT -> AC08