Drag with inertia _xmouse, _ymouse problem

I grabbed this script from senocular.com and modified it to suit what I am doing, which is creating draggable mc’s that slide after the mouse is release.
The problem I am having, and can’t seem to solve, is that when you click on the mc it sets the _ x and _y to _xmouse and _ymouse. It is because of this part of the script:

_x = _parent._xmouse
_y = _parent._ymouse

I really want it to act the same as the startDrag function, where the mc doesn’t reset its _x and _y coords to _xmouse _ymouse. If you modify it to be

_x = _parent._xmouse - _x

I dunno how to record and execute the offset… I assume that will be the answer.

Please help

Attach Code:
vector = [-_xmouse2, _ymouse2.5]
thisPos = [_x,_y]
dragging = true

type = “throw”
bounds = {left: 0, right: 1280-image._width*2, up: 0, down: 768}
vector = [0,0];

onClipEvent(enterFrame) {
if (dragging) {
_x = _parent._xmouse
_y = _parent._ymouse
lastPos = thisPos
thisPos = [_x,_y]
dragVector = [thisPos[0]-lastPos[0],lastPos[1]-thisPos[1]]
} else {
_x += vector[0]
_y -= vector[1]

dragging = false
vector = dragVector