newbie question about mask and content

[Trusts]

Hi,

I've taken over a Flash project. I have years of programming. ActionScript, PHP, etc. are no problem.

Anyway, I had a .FLA file open and somehow got a "content" (or maybe mask?) layer to "open up" revealing several more layers. I am not sure how I did this, but need to do this repeatedly to add text entry boxes in certain places. Later I will read the entries and process then with PHP. I think I can figure that part out.

But as silly as it sounds, does anyone know how to expand the content layer?

Thanks a bunch!
KB