Limit area for mouse action to pan

First, thanks to Kirupa for everything and the people in the forum, as a novice i have been learning and making progress. But as i am here i have not hit anywhere near the level i would like to be. So onto my prob. I have a code that i took from a file and i would like to modify one thing. The code below allows mouse movements to scroll multiple layers at different paces. The problem is that i want to limit the mouse movement area to just a center rectangle and not the entire stage. Is there something in the code below that would allow me to “define an area” for mouse movements to activate the layer scrolls. Thank you again for any suggestions or help!


var scrollItems:Array = new Array();
var mummLand:Object = {minX:0, maxX:2200};
var mousePos:Number = 0;
addScrollItem(‘FrgrdArch’, mummLand, 0, 325, -((Stage.width/mummLand.maxX)*110));
addScrollItem(‘BkgrdSkyline’, mummLand, 0, 331, -((Stage.width/mummLand.maxX)120));
onEnterFrame = function () {
mousePos = _xmouse/Stage.width;
for (i=0; i<scrollItems.length; i++) {
setDest(scrollItems
, .2, mousePos);
}
};
function addScrollItem(linkageName:String, environment:Object, offsetPercent:Number, startY:Number, iZ:Number) {
scrollItems.push(attachMovie(linkageName, linkageName, -(scrollItems.length), {_y:startY, env:environment}));
scrollItems[scrollItems.length-1].maxX = (offsetPercent/100)environment.maxX;
scrollItems[scrollItems.length-1].minX = ((100-iZ)/100)environment.maxX-scrollItems[scrollItems.length-1]._width;
scrollItems[scrollItems.length-1]._x = scrollItems[scrollItems.length-1].maxX;
}
function setDest(target:MovieClip, speed:Number, mousePercent:Number) {
target.destX = Math.round(-(target.env.maxX
mousePercent)+target.maxX+(target.minX
mousePercent));
if (target._x !== target.destX) {
if ((target._x-target.destX)>0) {
target._x += Math.floor((target.destX-target._x)*speed);
} else {
target._x += Math.ceil((target.destX-target._x)*speed);
}
}
}