I think I'm almost there. Everything seems to be working except the file that gets uploaded appears as .jpg, with no name in front of the extension. That's how it gets updated to the table and on the users_detail.php page where the image should be the URL is domain.com/cust_images/.jpg. I've tried each of the options in the "If file exists" option box, all with the same results.
I'm attaching the update page.