@petra-pik Or course I understand and I can be very patient. However, every time the widget fails on me, I will take the opportunity to remind you folks that the problem still exists, in case the bug gets forgotten.
I have managed to get metric_cbase="ft" pushed to the server from my desktop Chrome and get it pulled by the Android app in turn. So it should be sorted for me now, but don't tell me this is the only way how to do it! :-)