Help with this PLEASE!

i have my navigation half built ( and i am having a few issues.

  1. set the initial _x position?

  2. how can make the navigation ease to an _x position when you roll out of the swf?

  3. stop the movement of the _x postion so it cannot go too far left or right?

This is the code i have used. it has been applied to the black bar in the background and the white mask for the text

onClipEvent (load) {
    _x = 0;
    speed = 2;


onClipEvent (enterFrame) {
    endX = _root._xmouse;
    _x += (endX-_x)/speed;

This navigation will be used on an html site, any and all help will be greatly appreciated.