I’m having an issue to which I haven’t been able to find a solution just by searching here or on Google.
I’m building a project which is shared by multiple developer
I too have been having issues with storyboards causing freezes with XCode 6.0.1 on OS X 10.9.5.
I can't even start Xcode because it tries to re-open the storyboard.
Here's what I do to recover (until it happens again)
IMPORTANT: make sure you back up your storyboard file in case you accidentally delete it
At this point everything "usually" works for me: open the storyboard, build, run... I can keep working with the storyboard until the next time I re-open the project. Then it happens again and I have to repeat the same steps.