This issue is currently under investigation. Please remember, this is a beta OS and beta drivers, there will be issues discovered.
Thanks Robert, it is understandable. If you need more information for troubleshooting let me know.
On a side-note, I did notice that DXDiag also crashes on the Direct3D property page with this driver. The same is true for other Direct3D applications, so it seems to imply that the driver is not loading properly. System is Yoga 2 Pro, with HD4400 graphics.
An update: As of a couple of days ago the driver decided to load properly. I had left the computer to go to sleep and when it got out of sleep the driver loaded properly. Now everything appears to be working properly. Strange... (Unless a corrected version was pushed through Windows Update without me noticing).