New AE (2015) and new OS X are not compatible.
Adobe says they are... then they backtracked.
Get AE 2014. It's got some bugs and issues, too, but nowhere near as many as AE 2015.
Dissidently, the OP is not talking about CC 2015 - they've got issues with CS5.
Juliee, in your preferences, change the options for "use system color picker". That usually solves color picker crashing issues like you describe.
CS5 is officially "not supported" on the new OS you're trying to use. I would suggest either updating your AE to CC 2014 and/or CC 2015 or only use CS5 on operating systems for which it was intended.
Thank you for your respons. I tried changing the option to "use system color picker" but it made no difference. I also tried to updating the program, without succeeding.
If CS5 won't work on that system, you are probably going to have to either use an older operating system to go with your older software or get newer software to go with your new OS.
And now you understand my post...