Making XML Gallery Fullscreen

I am awful with XML so please accept my apologies ahead of time. I am using an XML Gallery on my website and I would like to make it full screen. I have played around with the code for hours and pulled most of my hair out and STILL I have no luck on making it fullscreen…

Here is my code used to align the holder on the stage and the gallery components (bttnPrev and bttnNext are on the left and right of the image to control movement to other images):

alignPic = function () {
	holder._x = (stageW-holder._width)/2;
	holder._y = (stageH-holder._height-menu_mc._height)/2; = holder._x; = holder._y;
	bg_mc._x = holder._width/2;
	bg_mc._y = holder._height/2;
	bttnNext._y = holder._y+(holder._height-bttnNext._height)/2;
	bttnNext._x = bg_mc._width+(stageW-bg_mc._width)/2-bttnNext._width-border/2;
	bttnPrev._y = holder._y+(holder._height-bttnPrev._height)/2;
	bttnPrev._x = (stageW-bg_mc._width)/2+bttnPrev._width+border/2;
	preloader._x = holder._x+holder._width/2;
	preloader._y = holder._y+holder._height/2;

Thx for any help, ideas or assistance!