1:1 Interview & presentation is only thing that matters,, You are expected to give a formal presentation to board of directors. It is about strategy and plan of action.
In one to one interview it is only about the business, and can last for more than 3 sessions of 6 hours of talking and lunch/dinner. Expected from you is scenario planning details in various cases.
Little discussion about legal and accounting issues are also asked. Your knowledge of history and macro issues matters. You are expected to give your credentials and background check to HR people who check for IQ/Psyche etc.