So I successfully moved my catalog (I thought), but as I started editing more from four days of shoots, it started slowing down, and becoming "unresponsive", till it finally got the to point of useless. This would happen in the Develop mode as it would try to update brush adjustments, when I'd switch to another image, or when I tried to switch views. I tried doing a reset preferences, no help. Checked all the things I could think of, and was almost to the point of uninstalling and reinstalling LR, when I thought I'd try a new catalog. Set up a test catalog, imported images, and it works fine again????????? I'm at a loss as to why it started doing what it did. Is it possible my catalog was corrupted???? I deleted several old images out of my files recently, but I always optimized catalog after doing the deletes. I was going to restore a backup but there were several new edits, that weren't on the last backup. So now I'm questioning whether to just lose the most recent edits, and go to the last backup, or try to merge the existing catalog into a new one??? Anyone else have any experience with something like this???????