vish320 - As per the Fragrant Harbour forum, posts dating back to 2009 suggest that after the final interview in Hong Kong, Cathay recruited around 70 cadets ('worldwide') for further flight training/grading in Adelaide. I assume it would be a similar figure this time. Tough competition, considering the recruitment process is ongoing in approx. 15 countries (if I'm not mistaken).
Dub32 - There isn't any specific forum to discuss the technical interview questions. Candidates who passed earlier haven't shared their experiences either. So don't expect much. Get on with your books and be prepared. Maybe 'Ace the technical Pilot interview' would help. That's all I can think of at the moment. Regarding the initial interview (technical + personal) , I'm pretty sure about the high standards they set when it comes to 'communication skills' i.e. a candidate's fluency in English.
Gibberish is a recipe for disaster.