I have finally found the problem and solved it - it is to my knowledge not mentioned in the new manual that one needs both cables together for the Nikon to make it work - the USB to connect and the shutter release cable. Both need to be plugged into the ASIAIR Pro and in the settings you can suddenly see that the camera is there and it works. I tried it today with the D810a, the D700 and the D850. The D850, I would not recommend because the files are huge and it takes too long for them to be transfered to the storage without some occasional problems. That means of course, that the storage of the exposures cannot be anymore on the large USB stick but only on the small 32GB one or on the camera, which I prefer anyway. But another small drawback is the fact, that storing the exposures on the camera´s media, it takes a bit longer than on the fast USB stick....but I can live with it...