[Craig]

What's happening is that the first couple of selectors over the right pane (Group and Sort) are about arranging, not filtering, actions - this is why, I think, Omni stopped calling the View Bar the "Filter Ribbon."

The documentation you're waiting for will come, as you mention, but in the meantime perhaps what you should ask Omni for is this new feature: In the middle View Bar selector, a "Due and overdue" option. Since that's one of the selectors that actually does filter, it seems like the place one could put the function for which you are asking.