You can run DataCAD on a Mac, using VMware Fusion, or Parallels Desktop to install Windows to then run any Windows program, including DataCAD. I did this for 8 years. You do need enough RAM to support Windows at the same time, so 8GB total would be minimum.
To rewrite the code for Mac would be a Herculean effort - it would take a long time, and it would cost you far more than the cost of Fusion and a Windows license.
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