The export is orienting the Entity I'm exporting in an unexpected (and unwelcome) way and I can't figure out why. I've never before needed the "Output Orientation" controls, but when I attempt to use them to remedy things I can't make them affect the orientation of the Entity within the DXF at all.
Furthermore, the orientation it's selecting doesn't appear to align with any axis / plane of the part. It's almost as if it's just trying to minimize the size of the bounding box for the DXF, though I can't imagine why that would be the default behavior...
Screen shot of UI with orientation it's selecting attached, as well as the original part.