Quick bit of code stick it on the first frame of new flash file and it will list all the FlashVars passed into the flash.

//creates the text feild on the stage

this.createTextField("vars_txt",3,100,100,Stage.width-100, Stage.height-100)

//sets the basic properties

vars_txt.multiline = true;

vars_txt.selectable = true;

//adds the title

vars_txt.text += "FlashVar : Contant of FlashVar\n";

for(var z in _root)

{

 //$version: version is on the root by default so it is excluded

 //vars_txt: is the name of the text field so it is also excluded from the list

 if(z !=  "$version" && z != "vars_txt")

 vars_txt.text += z + " : " + _root[z]+"\n";

}