Minor bug in chest shop when loading party after opening chest

If you open a chest in the chest shop, then load a different party, the sound effects of opening the chest replay, then there's a flash error afterwards. (Also, the chest color reverts back to brown)

Code:

RangeError: Error #2006: The supplied index is out of bounds.
    at flash.display::DisplayObjectContainer/addChildAt()
    at mx.core::UIComponent/http://www.adobe.com/2006/flex/mx/internal::$addChildAt()
    at mx.core::UIComponent/addChildAt()
    at com.cardhunter.pcclient::Displayable/addChildAt()
    at com.cardhunter.pcclient::Displayable/addChild()
    at com.cardhunter.pcclient.chests::StoreTreasureDisplay/finishDrop()
    at Function/http://adobe.com/AS3/2006/builtin::apply()
    at com.greensock.core::TweenCore/complete()
    at com.greensock::TweenLite/renderTime()
    at com.greensock.core::SimpleTimeline/renderTime()
    at com.greensock::TweenLite$/updateAll()