This from Adobe...
Flash Player is a language runtime. We process ActionScript written by the content provider, and do all the nuts-and-bolts stuff, like allocating memory and rendering pixels to the screen. Game developers often times push the edge of what's possible with Flash, and don't always write the most efficient code.
We make a performance profiling tool available for content developers called Adobe Scout that allows them to track what code is spending the most time on various activities, so that they can identify and optimize hotspots.
It's unlikely that there's a generic fix that we can make that will magically improve performance for this one game. The best course of action is to report the performance issue to the game developer, and encourage them to profile it using Scout. If they identify a specific problem with an ActionScript call that's super slow or something, they'll be able to isolate that case and ask us the fine-grained technical question necessary to either identify an actionable problem, or provide them with a recommendation on a better approach, etc.