It was suggested privately to me that I should try restoring all the camera parameters back to default settings. I tried this on one of my cameras. (For reference, both of my cameras are at firmware version 5.2.3) After restoring all parameters to default and rebooting, I used SADP to find the camera and change the ip address so that I could open its web configuration page in my browser. Before making any other changes, I tried configuring all four text overlays with text. Only the text in text overlay 1 was visible on the live view. In other words, it didn't help to set all the parameters back to default settings. As of this posting, the text overlay problem has NOT been resolved and it appears that it will have to be resolved by the manufacturer.