P: Merge to HDR and Panorama doesn't work

On a regular basis, I merge 5 bracketed shots from my drone.  In the older LR, this operation took about 1 minute or less.  I could "batch" 5 operations at a time and have them all done in about 3 minutes or less.

 

With the newer, faster, more awesome (and likely soon-to-be-deprecated) LR, it simply won't do anything.  I was lucky and had one HDR to work, but I've tried countless others (one for nearly two hours) and nothing happens.  The progress bar makes no progress.

 

I'm really worried that this important feature is simply victim of a bug.

 

Anyone else having issues?  Adobe, what's up with this??

 



I'm using a medium-powered PC that has never had problems with merge before.