Document Class Variables

I have a document class setting a variable called “_captioning”, being set to false. I have a base class being added that needs to check and see what this variable is set to when it is added to the stage. I can’t get it to read this variable at all.

I’ve been doing some research and found a post on this site talking about MovieClip(root) for this same problem. I can’t get it to work at all. MovieClip(root)._captioning will trace from in the document class but not the base class. If I try even tracing MovieClip(root) all I get is “null”. If I trace MovieClip(root) from the document class, I get [object MainEngineDocClass] (MainEngineDocClass is the name of my document class).

This thing is driving me crazy. Can anyone help?