Thank you. It works fine with several apps like Wahoo and others. Now I tried with TR and also: the Misuro is recognised as power meter without problems - great!
I went for a Ramp test and quite surprisingly I made it almost to my FTP I measured with the Kickr some weeks ago… encouraging!
And yes, it takes more to make it through the Ramp test on rollers…: the reason I quit the Ramp test was not yet completely my exhaustion… but me loosing focus on balancing on the rollers… and falling off
… i closed my eyes to fight through these last minutes (as Iused to do on the Kickr)… not a good idea on rollers 
Doesnt matter… i would have had to stop some seconds later anyway…
So: Misuro with TR App works fine and is probably quite consistent although certainly not as precise as real power meters… that is not so important for me.
Thx to all of you for the input.