I found that you must give a good answer to Herma Mora or when you get back to the Skall they will attack you. That is what happen to me after I made one choice so I thankfully made a save when I first enter the book level and made the correct choice. So when you are asked to get the knowledge of the Skall always so I will speak to them, with any of choice you may not be able to get the knowledge you are seeking. Has anyone ever had this happen to them.