Just redid some of yesterday's work and I can say that this Beta program, using a mid-2010 MBP, 2.66 Hz i7, 4 Gb RAM machine, and running MAC OS X 10.7.4 went flawlessly. As noted above, you must first install the 'mono' download, but after that, no problems. Ran quickly, and the only mior issue is connecting the cameras. First open the FOCAL program, then plug in camera USB, then computer USB then turn on camera, then 'connect' camera via software - which takes a few seconds, and maybe some plugging / unplugging of the USB port, but it did recognize 7d, 1d IV, 5d3 and 1d-x.
a few minor differences from WINDOWS format, but as a beta, no real complaints.