What consistencies can be attributed to the Monument Makers and their creations? Why is Oz seemingly different?

What is so important on Quraqua that costs Richard his life? Who pushed so hard for its retrieval and why?

Who feels directly responsible for Richard's death and why? Who are the indirectly responsible that should share the blame and why? Hint - there are at least three others.

What discovery is made on Nok that ties it directly to Quraqua? What common factor do the two worlds share that make it impossible for them to have been responsible?

How is the possible location of the Monument Makers discovered and by whom? How are the criterion reduced to a single likelihood?

Why does the Wincklemann leave early for their second mission? What might have happened had they left as scheduled and why?

Who is the first to...