I need some help. I have a mid 2010 macbook pro i got off ebay. This is my first macbook by the way. Anyway, it has 10.12.4 running on it. I have a copy of pro tool 8.3 that I want to run on it but it is not supported on Sierra. I would like to dual boot my macbook with 10.6 and 10.12.4. I partitioned 100 gb of the hard drive to run 10.6 and ordered a retail copy of 10.6 off ebay. I got it and held down C to boot from the DVD drive. It runs a while and them give me a small screen telling me that the computer needs to reboot. When I reboot it, it just boots 10.12 back up. What am i doing wrong. Thanks for any help you can give me.