Xcode storyboard greyed out

I'm new to Xcode and OS X dev and would like to try out using storyboards. I've downloaded XCode 6 Beta but for some reason when I create a new project (for OS X), the option to select storyboards remains greyed out.

I've attached a screenshot and hopefully somebody will know. Perhaps I need to download something extra, but not sure.

enter image description here

Thanks!

Solution

Storyboards for OS X only work in Yosemite and above (10.10). If you are running Xcode 6 in something lower than Yosemite you will see storyboards greyed out like in your image. There is more info in this SO question found here: Storyboards for OSX App in Xcode 6