You are getting that message because you're using flash debugger instead of regular flash player.
Originally Posted by Kappa3000
Other than that, its just a bad coding example, quite alot of trainers/bots load the background incorrectly.
As a matter of fact, they are reusing some code from the client itself, to be more specified the game.loadTitle func.
var _loc_2:* = titleDomain.getDefinition("TitleScreen") as Class;
_loc_1 = titleDomain.getDefinition("TitleScreen") as Class;
^ this wont dismiss the errors that the game spits out
titleScreen = event.target.applicationDomain.getDefinition("TitleScreen") as Class;