It seems it was a problem with the XYSurface of my panel, as I haven't been able to replicate the behaviour in another panel. After copying the XYSurface and paste a new one the problem has gone.
But I still don't understand how to use it. I see no midi out from the XYSurface when I move the dot.
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I can't reproduce this, it all works the way it was designed for me. maybe you can provide an example panel.
It seems it was a problem with the XYSurface of my panel, as I haven't been able to replicate the behaviour in another panel. After copying the XYSurface and paste a new one the problem has gone.
But I still don't understand how to use it. I see no midi out from the XYSurface when I move the dot.