DXF and DWG Export Options DialogKeyCreator \ File \ Export \ DXF-DWG-Export \ DXF-and-DWG-Export-Options-Dialog
The DXF/DWG options dialog appears when the OPTIONS button option is selected from the Export Options dialog.
"AC" in the name of this check box stands for "AutoCAD." When you select this option, all of the geometry in the KeyCreator file is flattened to a single layer in the exported file. This is useful for exporting layouts.