I am a swedish church musician, I am new to this forum. I don't know if I have posted this at the right place...
In GPO2 I was able to mix two instruments in one channel, and transpose one of them. That worked fine with Kontakt Player. (eg Principal untransposed + principal transposed one octave lower - that made an (virtual) registration Principal 8 + 4).
I cannot find how to do this in GPO4 and ARIA, and that is a pity, because I want to register my own organ. Another example: flutes + flutes transposed one octave lower made a beautiful pedal chorus 16+8+4.
Am I wrong or has that option disappeared?