I have tried to double process an image in PS. I use the "open image as a Smart object" in Light room this works. I can use the "Create Smart Object via Copy" in PS but, as soon as I double click the thumb nail to open the file in Camera Raw, my computer freezes on a black screen. Has any one had this kind of problem?
As I understand when you try to open an image from Lightroom in Photoshop's camera raw, the app completely stalls and shows you a black window, but when you select the option "Open image as a smart object" it opens perfectly fine.
Have you tried opening the same raw image from finder/explorer into Photoshop directly, which should ideally open it directly into the camera raw panel?
Also, Which version of Photoshop, Lightroom and camera raw are you using?