Please try turn off the Graphics Processor from Lightroom Preferences.
Click on Lightroom on the top menu
Go to Preferences
Click on Performance tab
Uncheck the Graphics Processor
Restart the Lightroom
Also follow the below article.
Once you perform both step, then try and use the Lightroom.
Let us know if that helps.
Hi Mohit I still not able to get the Pano to work . The screen still shows black . Is there a way then I can revert back to LR 6.1? Or Adobe is coming out with a solution soon ?