Rapture synth has a modified, and not true, multi-timbrel feature. The feature allows for the six Elements to receive independent midi tracks. For example, You can play a lead on Element 1, and you can play a pad on Element 2.
In Ableton Live, you simply click, “multi-timbrel,” in Raptures Global Screen, then you can route midi tracks to Rapture – 1 - 6.
How would you accomplish in Renoise?
Perhaps in the Renoise manual, there is more about routing, midi, and etc, but the manual is very large, and I am still studying.
Thank you