Hi K1 - it's dead easy.
I'll assume you're using L8.
* Pull up your environment and either create a new layer or use an existing one.
* From the local menu, select New>Channel Strip> Auxiliary
That wil create a new aux strip for you. When I do this, for some reason, L8 switches to the audio layer and puts it there. Don't know why. I just cut and paste it to the layer I want to use.
Once the strips are in place, go back to UB and assign the samples you're using to the various output channels. You do this by selecting 'Main' (the default) next to the voice and making your selection.
When you have your voices assigned, go back to the layer your aux channels are on and configure their inputs (I/O) to the appropriate UB outputs specified above.
I created an explanatory pic of what to, but I don't think this forum configuration lets me include it in the post. I can email it to you if you wish.