[DaVu]

Is there something I need to do to make these settings permanent?

Yes. next to the fact you should update as mentioned, you should also take a look at your TV manual. That overscan issue is mostly caused by a TV setting. Using the screen calibration inside Kodi should only be your last resort. You should check the zoom-options from your TV first or see if it has something like a PC-mode or similar. Manufactors do have different names for overscan on your TV. So without knowing the exact TV model you are using, I can't be more specific. If you mind, please name it and I'll do a little search if you are able to disable overscan on your TV completely.