It's very simple. You can use a limit order to MAKE money, NOT to prevent you from LOSING money.
So if you have MOVIE stock buy at $50, and you want to sell it if it goes to $60...set a limit order to do that.
If you short MOVIE at $50 and you want to sell it if it RISES to $55, it will execute right away since you can't use limit orders to prevent losses...only to make profits. There is no stop loss ability in HSX.
Hope that helps.