A couple of days ago, I replaced a radio button element with a combo box in a prompt set. When I tried to save the prompt set, the JUI popped up error U04006531. The list of properties on the left side of the prompt set window went completely blank. I was able to edit the prompt set without problems in the AWI. Today, I cannot reproduce the problem. I know I've seen it before, years ago. Has anyone else seen this?