Has anyone downgraded an iMac 5 (Retina 5k, 27-inch, Late 2014) pre-installed with Yosemite to an older version of Mac OS?
My Pro Tools 10 does´t work with Yosemite. I have two days to resolve this, if not I have to return the computer.
I have tried it to downgrade and it appears this symbol:
If somebody has done the downgrade, please give a step-by-step solution.