You can program pretty much any polyrhythm (anything from 1 note per bar to 64 notes per bar against each other)
However, you can’t program note groups over odd numbers of 1/4 notes. For example, you can’t program 5 over 3 quarter notes in a bar of 4/4.
The user interface required to make this possible would be extremely complicated to understand, and there aren’t many people who need to do this.
If you want to hear what 5 over 3 notes sounds like you can do it by programming 5 into metronome1, and 3 into metronome2.
Essentially you’re hearing 5 over a bar against 3 over a bar. I know this limitation means you can’t program some of the complex Gary Chaffee patterns. Sorry about that.
You can, however, use it to hear what sections of those bars would sound like.