blueram,
Treat the skype interview as a regular face to face interview. Make sure your webcam works, you are dressed in business professional attire (including wearing pants and shoes - in some cases, students were asked to get up and turns out some did not wear pants.....another story for another time).
The interview will be very relaxing - it will be very conversational..
things to remember
1 Read your CV and remember all bullet points you have listed - anything is fair game and if you cannot explain things on your CV then too bad
2. Read your essays and remember them well - adcom will ask you questions regarding your work experience, or handling conflict, challenges, team leadership from the stuff you have written in your essays.
3. talk about international experience, diversity, why MBA, why now, why at HKUST.
4. ask questions about the program - do some research on the program and do come up with some good questions - not generic types
5. interviews will be on background and personality - adcom is not going to ask what sort of exotic derivatives you structured if you were a trader at a bank. As I have said before, the interview is all about fit.
good luck with the interview.