I suspect that maybe every different program that saves or exports a so-called "AutoCad" .dxf may not save it exactly the same as Autocad and I also suspect that most of the testing, if not all, of LCAM has been done with files that weren't generated with ACAD (am I wrong? I don't know!). There must be some subtle differences that account for why some files load and some don't. That's my guess. And that's all it is -- a guess! Unless LCAM gets revised to except any .dxf file from any source, I'm guessing that we all have to find our own way of getting our files loaded. Once they do get in there, it sure is an easy way to get your G-code output (in spite of the bugs that still exist). Makes it all worth while!