First, I'm a Windows user, so doing this from memory....
Did you install the old Java? I seem to recall reading that older versions of ID require and older version of Java to also be installed. This goes along with the question, did it ever work on this OS? Was it a clean install on this computer, or a migration? Migration does not work for ID and you must uninstall, run the cleaner tool (CS Cleaner Tool for installation problems | CCM, CS6, CS5.5, CS5, CS4, CS3) and reinstall, but I'm not sure that there is official support for running CS5 on 10.10 so you may encounter some issues.
Finally, the particular crash you are reporting is a user library issue. See