Do overtone settings affect sympathetic resonance?

Thank you for pointing this, you are perfectly right. This is something that we will correct in a future release, we just forgot to update some parameters. Btw, when you change the spectrum, it changes the exciting notes, not the excited notes (this is because the modification applies to the voicing process at the hammer-string interaction level). Thus the most direct experience will be: hold down G4, hit C3 and play with the 3rd overtone (thus the 3rd overtone of C3 acting on the fundamental of G4). The other way, you will be observing the third overtone of G4 acting on the 9th overtone of C3, more difficult to hear.

Etalmor, yes, this will be done.