Download of EXDXF-Pro 4.5 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. EXDXF-Pro for Mac is categorized as System Tools. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe.
From the developer:
EXDXF-Pro provides you with the capability to import CAD-standard DXF files to Adobe Illustrator, and to export AI files to CAD, allowing you to make your data compatible in both applications. Illustrator CS2 includes basic DXF/DWG import and export functions, but the translator of Adobe Illustrator may not recognize or convert lines, curves and objects as you desire in every case.
You may want to check out more Mac applications, such as Open.nuke folder, d-d Zone or Butterflyzer, which might be related to EXDXF-Pro.