Del Harris suggests this drill in Coaching Basketball's Zone Offenses (1976)
First, he builds in constraints...(from the split over). The defense moves and reacts as a conventional zone would.
Next, he encourages cutting with passing (give-and-go, v-cuts, circle/bury)
He allows dribbling into gaps (punching) and driving. Although he doesn't specifically address screening, we can use or limit it according to our preferences.