Thank you for the quick reply, Walter. I will consider your cell-array tip in the future for a more robust GUI.
Just before your email arrived, I solved it. I went to the zoom box for the String property of each radio button, highlighted from the "bottom" to the last 2 characters of the entered string, hit delete, then retyped the last 2 characters. I guess some kind of hidden character (line feed?) was added to the end of the strings, so my odd method removed it.
Thanks again for your time.