What is CPM vs CPM Pay: what's the difference?

CPM (Cost Per Mille) is a metric showing how much you are effectively paying per 1,000 views, based on all configured payments (base pay, milestone bonus, etc.). CPM Pay is the specific payment column that you actually use to pay creators based on a CPM configuration. Only CPM Pay is tied to an active payment configuration. The general CPM columns are informational metrics only.