I had Beta 4 running fine on my MacBook Pro 2014, and this afternoon I download Beta 5 and it started the update process. However, when I came back to the laptop, it was still on a black boot screen, with the Apple logo, and the progress bar at 100%. I let it sit for a while, and finally turned the laptop off using the power button. I started it up again, and it kind of goes straight to the progress bar at around 80%, and then up to a 100, and then it hangs. I have let it sit for a long time. I have now restarted into Recovery mode to check the disk using disk utilities, and all is fine. However, when I boot again, the progress bar goes to 100%, and then the laptop hangs. What's going on???