Messages and commands are nearly identical: they both have a name,

they can both have parameters stashed in a table, and they both play
stuff out of the actor command list.  Merge them; now the only
difference between playing and broadcasting a command is that playing
plays recursively on a tree and broadcasting sends to all subscribers.

The distinction between "messages" and "commands" is cosmetic now;
everything is a message.  The only thing special about commands intended
to be received as a broadcast is the "Message" suffix, which subscribes it.

stepmania/src/ScoreDisplayAliveTime.h

@@ -19,7 +19,7 @@ public:
 	void LoadFromNode( const XNode* pNode );
 	virtual ScoreDisplayAliveTime *Copy() const;
 
-	void PlayCommand( const RString &sCommandName, const LuaReference *pParamTable );
+	virtual void HandleMessage( const Message &msg );
 
 	void UpdateNumber();