Mac users have been able to run either a dual boot with windows or a windows emulator such as Boot Camp which will allow windows to run in parallel with your macos.
PCB123 running on a mac is not supported, but you should be able to get it running with little or no trouble.
Bob Tise Sunstone Circuits
13626 S. Freeman Road
Mulino, OR 97042
Phone: 800-228-8198
Fax: 503-829-6657