Xcode 6 GM crashes when selecting the main storyboard or a xib

Question

I just downloaded the Xcode 6 GM and every time I select the main storyboard (and a specific xib) Xcode crashes.

The error to be sent to Apple contains the following

Answer 1

(1) Have you cleaned and rebuilt the project?

(2) Have you tried to empty the xcuserdata folder? The folder contains ui states and can be the reason for such an issue, especially when xcode was updated. The xcuserdata folder can be found in your project directory when you right-click your .xcodeproj "file" and select "show package content". Close Xcode, empty the xcuserdata folder and reopen the .xcodeproj file.

Hope one of these helps :)