hey guys, I'm trying to downgrade from Mountain lion to Lion on a macbook pro Retina. But from what I've read, some have said that Macbook pro 2012 would only boot and install a specific version of 10. 7. 4 . So is there more than one version? I already have 10. 7. 4 of Lion on a usb stick but just don't know if its specifically for the 2012 macbook pros.