See the image above to find what this screen looks like.
So there fix is quite simple really:
Just restart your device. Not once; not twice; but 4 times minimum.
I hear from a reliable source that RIM actually put in an error reporting mechanism that sends back information to RIM Dev team on ways to improve the BB 10 Dev Alpha.
I have restarted mine 4 times. It is finally back up J
Ok Gang, back As You Were.