It's probably related to this error that I get when I load the movie:
TypeError: Error #1009: Cannot access a property or method of a null
object reference.
at mx.containers.utilityClasses::CanvasLayout/measureContentArea()
at mx.containers.utilityClasses::CanvasLayout/measure()
at mx.core::LayoutContainer/measure()
at mx.core::Application/measure()
at mx.core::UIComponent/measureSizes()
at mx.core::UIComponent/validateSize()
at mx.core::Container/validateSize()
at mx.managers::LayoutManager/validateSize()
at mx.managers::LayoutManager/doPhasedInstantiation()
at Function/http://adobe.com/AS3/2006/builtin::apply()
at mx.core::UIComponent/callLaterDispatcher2()
at mx.core::UIComponent/callLaterDispatcher()
J
