Gyroscope
In general I find creating asset items around the origin to be the safest. When you're in your scene layout phase then you'd probably translate an object. So your model being 64000 units away from the origin in AutoCAD may be a problem but I have no real experience with AutoCAD. I've had some DXF files load (no errors) but nothing show, and others show curves. It probably depends on the export settings.
Does AutoCAD have the option of exporting IGES or STL? These are more widely accepted. I think STEP is a SolidWorks file format. With Polytrans, try it out, they have a demo, and see if it works for you.
I want to keep it at 64,000, as that is the distance from the origin that I need to revolve the profile around. The whole drawing does have lines going right from the origin to 64,000, so it's not totally empty around the origin and I've tried importing the complete drawing, too.
I managed to revolve the profile in Maya, then tried exporting using the 3 options at the bottom: SPF_DCE, STL_DCE, and IGES_DCE.
The IGES wouldn't work (I think it either gave an error or simply didn't create a file), but it does save a file if I create a new file with a simple object.
The STL saves an empty file, even with a simple object like a native Maya cylinder. And I made sure I used “export all” each time.
The one that did work was SPF/.wire. It didn't work the first time, but I might just have made a mistake the first time.
AutoCAD does have an STL option (called Lithography) but it asks for “solids or watertight meshes”.