Some things are similar in Pro7 to how you did it in ProPresenter 6; others are different. This is how you work with and assign screens in ProPresenter 7. It’s not like how you did it in Pro6.
First, while you can access it in ProPresenter Preferences, it takes an extra click to do so. So, in ProPresenter 7, you’ll want to go to Screens and then Configure screens.
Now, if you have ProVideo Player, you’ll notice that adding screens is very similar to how you do it there. If not, this is gonna be a whole new way of working with screens.