Updated to FCPX 10.2, can't get past splash screen

So, I got through a batch of projects, and finally upgraded to FCP 10.2

After installation, I can't get past the splash screen. I'm asked, via a dialogue box, if I wish to update my libraries / events. I do.

Then... I see rapid fire text loading and then updating libraries / events. Then it gets stuck on a particular event... beach ball... nothing.

I've tried several times, and it gets stuck on a random event.

I can't get past the splash screen. I've rebooted. Still nothing.