The issue mentioned in (1) in the first post of this thread relating to the Device Manager dropdown menu has been fixed in Nuendo 6.0.3.
The issue in (2) relating to recalling presets for External Effects and Instruments also appears to be fixed in N6.0.3.
I’m not sure about the issue in (3) relating to Creating Midi Devices as I currently have no Devices I need to create, but some work has been done on it judging be the changes in the documentation, so it too may well be fixed.
It has taken Steinberg a very long time to get around to these things, but they got there in the end.
Well done chaps!