What computer are you using?
Does your computer meet the minimum standards for running Color? (Link to standards)
Does it have dual monitors? (It should and each should be at least 1650x1050)
What is the format of the material? (It should be ProRes.)
And so on.
And yes, it does run in ML, though I don't trust it in that environment. I run it under 10.6.8 on a MacPro with a Kona card to feed the external reference monitor.