I did my further experiments with Origin KB and this time I tried to play KB with general level "local off" and route midi back to Origin. While there's relatively few stuck notes, it has problems. (And as you know, for real usage this must work 100%. On stage there can't be stuck notes).
I recorded all midi events with MIDI Monitor app and here's what happened:
Everything was fine quite a while, I could play both Origin itself and Virus without problems. Suddenly there was stuck note and in fact every note after that was also stuck note. MIDI Monitor revealed the obvious reason: Origin KB somehow generated Hold pedal message with value 127. This is strange because I had no any pedal(s) connected.
So there's some obvious bugs with MIDI out handling. As said earlier Origin seems to deal perfectly with incoming midi.
I continue my further MIDI tests and it would be great if other Origin KB users could do the same. Hopefully this helps solving the problem. As I said earlier, IMO this is so basic functionality that it should be at highest place of bug fix list.
And here's little more about (system level) "local on" MIDI problematics:
Midi stuck notes are most obvious and most easily re-created in multi presets. And (at least in my Origin KB) you'll have the for sure if those active zones overlap each other. Let's say you have a multi with four zones active with midi channels 1,2,3 and 4. If play just one note and record it with MIDI Monitor this is what I see: four Note on messages (ch 1,2,3,4) but just one note off message (ch 1). And this happens every time. There are other strange midi events but this is the most obvious case.
On the other hand, till now I haven't managed to generate midi problems in program mode. So if you wanna record your playing to sequencer I'd suggest to use program mode at the moment...