Fixed: Photomerge panorama says select 2 or more photos

When trying to get Photomerge panorama function to start in Photoshop Elements 15, I kept getting the message "Select (Control + Click) 2 or more photos in the photo bin..."  Well, I WAS selecting 2 images.  Things went a lot better after I changed the image mode from bitmode to grayscale.  Just thought I'd post this for others' information.