I am having a problem installing OS 7.5.3 on my CC with Mystic upgrade. I installed OS 8.1 a while back before I knew that a hack was required to allow OS 8.1 to work on a CC. Now, I wish to install OS 7.5.x back on my system, but I keep getting an install error. I downloaded OS 7.5.3 off of Apple's old software webpage. Now when I attempt to install the OS I get the following error message "This startup disk will not work on this Macintosh model. Use the latest nstaller or update this disk to the latest installer." Does anyone know what is wrong and how I can get this to install? I have an OS 7.5 CD that came with my CC when I bought it on eBay, but it won't install I get an error that the version is not for that system or something like that. I'm hoping to be able to install 7.5.3, but right now I keep getting the above error. Can anyone help me with this? I'm also fairly new to the MAC, so I don't know too much about the OS or any tricks to get 7.5.3 to install properly.
PS: What is the best OS version to use on a CC Mystic? I heard 7.6.1, is that true and if so, where can I find OS 7.6.1 I did not see it on Apple's old software website.