Daminion can import AutoCAD DWG and DXF files, but it’s hard to find the right drawing visually because the preview of these files is a default icon rather than a quality thumbnail.
However, if you download and install the free DWG TrueView from the AutoDesk you will be able to view quality thumbnails your AutoCAD DWG and DXF files, not only in Windows Explorer but also in Daminion.
AutoCAD thumbnails that still appearing as default icons can be rebuilt in the following way from the Daminion menu: Item > Rebuild Thumbnail (Ctrl + B)
If the thumbnails are still not displayed, make sure Windows is set to display thumbnails:
Go to the Windows Control Panel > Folder Options > View tab.
Uncheck “Always show icons, never thumbnails” and click OK.