I will also echo the comments that have already been made about the interview as a whole. Personally, I found the behavioural questions were the most challenging - the questions REALLY make you think. I'd advise thoroughly reflecting on past experiences (work, volunteering, group assignments in school, etc) in order to provide concrete examples for that portion of the interview.
I would also suggest reading up on some courses offered by the program and trying to find parallels between the subject matter and your end career/academic goals. They really do want to see if you have a clear vision in mind for yourself and have an understanding of how this program in particular can help you achieve your personal goals! ***
Overall, with adequate preparation, I'm sure you will be fine! Good luck to everyone!