Thanks very much for that quick response ... and pressing the button while putting the baattery back in DID give me a flash of all the leds and then, only once, continued with a flaash of the green LED three times.
I guess I missed or misunderstood the need to press the button AS the battery is being inserted.
The puck still isn't recognized by my chromebook's pairing but it is recognized by my samsung phone ... although the phone says I need an app to use the device ... and also by the espruino web ide.
Do you know if there's an espruino version of the madgwick ahrs protocol?
And the IDE says a new firmware is available. I have 2.09 and it's suggesting 2v16.
Do you know the firmware upgrade method? I'll look in the docs as well.