I finally solved the problem, and I can say the ASI120MM *IS* compatible with Mac / OSX with or without Virtual Machines.
I've done several tests, including download of the SDK and compiling it with new/updated drivers.
In the end this is the procedure to make it work, at least on Yosemite:
1) connect camera to the mac (no drivers available or needed)
2) download oacapture (latest is 0.8 beta), launch it, disable preview. Change exposure to 10ms or more, and max resolution, so you'll have a max theory FPS of about 35 (you can change this later but first make it work)
3) the camera will not work immediately (or will drop frames). Wait a few seconds, open Settings/Camera, change the USB traffic to 50, disable USB traffic (auto) check, and disable the High Speed. As soon as you change the USB traffic to 50, you should start seeing an FPS between 8 and 15, depending on your machine.
4) enable the preview. If you see some irregular squares appearing, change +1 or -1 the USB traffic, that is what makes oacapture 'reset' and camera will work without problems!
5) if you want to enable 16bit, you have to do it now: enable it, frames will stop, to 'reset' oacapture just enable and disable again the 'high speed' in Settings/Camera.
Now you can tweak with settings/expsorue/ROI etc., every time oacapture seems stuck or something is wrong, try changing the USB traffic of just 1 unit, and enabling/disabling high speed, and it will work again.
NOTES: if you enable 16bit as described above, and you close and restart oacapture, 16bit will be enabled BUT IS NOT. You need to disable it, and enable it once the camera is connected to oacapture: when you disconnect from oacapture then is back to 8 bit. Please notice that .SER produced on my setup at 16bit via oacapture seem wrong, so I think there's a bug in oacapture correctly recording 16bit.
This is the option I prefer, because you have Firecapture and Sharpcap. Procedure is simple:
1) launch oacapture and do steps listed above till the camera starts sending frames and you see it's ok in the preview (any setting is fine). This is because oacapture loads on the camera a firmware that is valid and working in the virtual machine, that is unable to do so
2) without disconnecting the camera from the usb, just disconnect it from oacapture. Start Parallels (virtual machine that I tried, with Win XP SP1 32bit), and after you install the asi drivers, start either Firecapture or Sharpcap, making sure you start at 10ms exposure and then you tweak it later. In both programs the camera will work perfectly, and you can achieve up to 10fps and max resolution/16bit! On my Parallels I have USB3 enabled.