Newbie question about identifying main timeline variables

I have been experiencing a seemingly odd problem. I am creating my program in flash, using keyframe animation. I have a movieclip that displays text. Originally the clip was added to the stage usinng flash, now I have add it using actionscript (addChild). The problem that needs fixing is that when I instantiate the movieclip in my set-up frame, it appears to be running all the code on the first frame of the movieclip (if this is not how things work, please correct me). Because of this, all the code on that frame that uses variables from the main timeline throw type errors, becuase they are identified by MovieClip(root) and there is no root for a movieclip that hasn’t been added to the display list yet (again correct me if i’m wrong). The detail that makes this seem odd to me is that it worked fine yesterday. Then I changed some other code that has absolutely nothing to do with this textbox and I start to get a bunch of runtime errors (and I didn’t log those changes well enough to go back and see what code I edited that may have caused this change). So my questions are this:

  1. Is there a way to identify variables on the main timeline other than with MovieClip(root)?
  2. Is there another way to fix this, say by having flash run that first frame of code when the clip is added to the display list rather than instantiated?
  3. Does anyone know of a reason or glitch that would have caused this to work for a while then stop working?