Hello fellow Mac experts. I have a Mac Pro 5,1 (six core) running 3.46 GHz Xeon and 32Gb RAM. My main boot disk is Windows 7 (don't ask me why) and my second boot disk is OS-X 10.9.5 which I select using the option key when I need. My 3rd internal HD is used for the Home partition for OS-X and the fourth and last HD is partioned in 2 equal sized chunks, one for time machine and the other for Windows 7 backups. Finally, my questions: 1) Can I update to Yosemite on the OS-X boot drive without messing up the other ones; 2) Will I be able to continuing booting to Yosemite using the option key, and leaving Windows 7 intact as main (default) boot disk; 3) Will Logic 9 and Final Cut Express (older version) work under Yosemite? Thanks in advance for your reply.