I couldn't seem to get the Panel to work for me for some reason, so I played around with it and startet digging.
In this process I found a bug that affects localised hardware, where the decimal symbol is not a point.
To get the example running I had to do the following:
Set "use system decimal point" to false
and
Set the options on the formating string to use the decimal point.
There might be other instances of the GetJSONData Method where the format has to be changed, I didn't check all of them.
Cheers,
Robert