ROBOTC will work on a Mac with any of the Windows Virtualization/Emulation software packages that are available, example software includes Parallels, VM Ware Fusion, Boot Camp and Virtual Box.
MAC OS 10.8.1 "Mountain Lion" Running ROBOTC with Parallels Virtualization software
Once the software is installed, installation and activation are exactly the same as on a normal Windows PC. Please see your software's documentation regarding connecting your USB devices to your virtual environment.
For more information on various Virtualization software: