The Harbus, the student newspaper of HBS, publishes a list of approximately 100 real MBA interview questions, accompanied by detailed analysis of how to answer them. It's the only guide out there that is written by actual current MBA students, so it is straight from people who have actually successf...

Even in past years many invites have gone out in the second wave and many students in that wave are ultimately accepted. So you shouldn't overthink it.

There's a lot of helpful information in the HBS interview guide:
www.harbus.org/admissions-guide/