This might be an OS issue. I'm using Lightroom CC on Windows 10, and the panorama feature works fine. There are apparently a number of issues with Lightroom running under El Capitan.
Please go to the preferences of the Lightroom and under the performance tab, and uncheck "use graphics processor"
Restart the Lightroom and try again.
Ok, Thanks for the replies.
The graphics processor wasn't the cause, I already checked.
I think I'm waiting for an update of LR which hopefully fixes this issue, otherwise I try rolling back to a previous version.
Well, for what it's worth, I have latest Lightroom CC installed on my Windows 10 computer, no graphics card (Intel integrated graphics). I just went in and tried again and created a 12 image panorama. I didn't get the black screen. The panorama image was created as expected.