Did the full reset as described so excellently above. The panel came back to life and told me to do a calibration. The screen responded instantly and said Calibration Successful. So far, so good. The demo software then appeared and things were as broken as ever. Sometimes a button would respond instantly, other times it would go to its depressed-state and just stay there, like I was holding my finger on it. For instance, after a lot of touch-screen-touching I finally got into settings. Swapping between General / Screen / Info is as snappy as ever with the Page +/- buttons, but with the touch-screen it's just painful. Seems every 30 touch is registered. It would lead me to believe that the touchscreen is broken, has intermittent connection or is just plain worn out, but that doesn't explain the times it hangs for minutes without responding to anything or when it says "low battery" and hangs for minutes even though the battery is new and fully charged.
