Okay, I could be totally wrong but i'll try to answer these ones..
1: Flying is regulated by the Hong Kong Civil Aviation Department.
2: Allowable time? (i don't know this one, I would only guess that its 100 hours per month ? )
3: CX retirement is at 55 in the PAX fleet. Dragon Air is at 60.
4: Hong Kong Dollar is pegged to the USD at ~ HKD$7.8 = USD$1. The Hong Kong Monetery Authority tries to keep it at that rate. But there is no absolute guarantee that it will stay at that rate forever.