That's a known issue/quirk/fault.. call it what you will..
You should be getting the green LED around the firing button when you plug it in to charge and that green light will go out when the batt is fully charged.
As to the two button blue display, if you push both buttons while it is charging, you will see the resistance of the coil that is in place (or non if no device is attached) and immediately after that the current state of charge (batt voltage). But it works once only, for some reason. Take it off charging and the display will light up again as usual. Just a quirk. HTH
Yup, that's what I needed to know. Thanks!

That is quite a lot of stuff. My girl would kill me if my collection grew that large haha. She already calls me a hoarder. I say that I've outgrown my condo (which is a fact, I need a house!)