Xcode 5.1.1 crashes on 10.9.5 Mavericks when run in User Account but runs in Guest Account
This would seem to be an answer, but as my situation was resolved when I updated to 10.10 I cannot test to prove it, but share just in case it proves to be useful

https://stackoverflow.com/questions/22480382/xcode-5-1-doesnt-load-on-os-x-10-9-2-and-10-9-3/26704775#26704775