If the flights are all on 1 PNR, then MH in SYD will check all the way through to AMS. If the SYD-KUL flight is still an A330 then it will arrive at the Satellite terminal, which is also where QR will depart from. Satellite terminal has four arms, easily walkable in 10 mins. Security is done at the gate entrance, which will probably take the most time out of everything during your transit.
The main terminal, I believe is only set up to accommodate narrow body aircraft, so 737’s. If it does happen to arrive at the main terminal, there is a monorail to the satellite terminal.