I have a new but refurbished mid-2011 iMac which originally was built with Leopard 10.6.6 according to Apple info but this refurb came with Lion. I am needing to install Final Cut Studio 2 but get that common problem of Lion not allowing it. It has to be installed on Leopard, or, something called Rosetta inside Leopard has been installed on Lion by some with Leopard discs. I don't have a Leopard disc, only a MacBook Air usb Reinstall drive with Leopard 10.6.6. So, I set a partition for Leopard but can't get anywhere near the point where I can install Leopard on it. I can't get that drive to start up after it prompts the restart. I just get a gray screen with apple logo. I pressed c key during Apple's opening startup tone and also tried option key but neither are working. Option key gave me choice to choose usb as startup disc but nothing happened after that, screen went gray. Thanks for your help!