Best import filter in LazyCAM for CorelDraw files

I do not have a dedicated CAD program for creating DXF files for use with LazyCAM. I am currently using CorelDraw X3, and have tried exporting files in each of the supported AutoCAD DXF formats: R13, R14, AC2000, AC2002, and AC2004. I have also tried exporting the files in EACH of the supported vector formats for various other programs such as Adobe Illustrator, HPGL, Windows Metafile, etc. The ONLY format which would allow me to successfully import the file with circles and arcs appearing in LazyCAM as actual circles and arcs (instead of obscure Octagons) is the Windows Metafile format. However, all scaling is LOST in the process. I created a "Test Pattern" in CorelDraw which contained a 4"x4" square with a perfect circle 4" in diameter centered within the square, with a horizontal line, and vertical line, and two lines at 45 degrees all intersecting at the center. When I opened the file into LazyCAM it measured 5,988.00 x 5,988.00 units in size! Can anyone help with what file format to use for the export FROM CorelDraw X3, and which format to use for opening the file FROM LazyCAM?