Trouble with global variable!

i’m having a hard time getting my global variable to work with my xml gallery.

i have a button which has the url of the xml file I want to load, so when I press the button the gallery will display the xml file I chose.

here’s my button code:

    _global.GALLERY = url;
    //url  = gallery1.xml

and the code in another clip for the images is:


I have a feeling im plain doing it wrong.
any ideas?? I hope this is pretty basic.