Here's the first two problems they offer in the paper:
In Problem 1, the "Given" and "Prove" are missing. In Problem 2, the diagram is missing. They seem to have made a big list of things that can happen in geometry proofs and designed problems by excluding some combination of these things. It's the job of kids to provide those missing things.
In Problem 4 it's the actual given statements.
In Problem 5 it's the theorems.
In Problem 6 it's the auxiliary line.
The last three problems are a bit different. In Problem 7 they explicitly ask kids to make conjectures -- something I know that I should be more systematic about than I have been in class. In Problem 8 they ask kids to find mistakes in a given proof. Problem 9 is another "missing information" problem, where this time they left out the theorem but gave you the entire proof.
This past year I really didn't push my classes to do much written proving -- though "how do we know this?" was practically a mantra in my teaching -- but I was often disappointed by my students' ability to write down logical arguments when I did ask them to explain their thinking on paper. I think that these scaffolds could be an important part of what I do next year.