I've had the same problem. But finally the solution, for me, was simple.
First, i've recovered the the "connect to itunes" mode.
As said before, once you install the new Xcode 6 beta 6, it brings changes to itunes 12 that repairs this crash problem.
So, install Xcode 6 before by downloading it and opening it once.
Having the exact problem with the original post, and I'm downloading Xcode 6 beta 5 to try out this suggestion. At the same time I'm getting my PC ready in case this does not work.