f6 to f7 / can't get it converted

found an old file and tried to publish it in f7 - as you expected it wouldn’t work
checked for case sensitivity and all
i suppose it’s the ‘with’ line in the code but my as talents are very limited
maybe someone could help me

Movieclip.prototype.repel = function() {
	var maxDistance = 150;
	var power = 80;
	var friction = .2;
	var ratio = .20;
	var maxD = maxdistance*maxdistance;
	var a = power/maxD;
	var distancex = _root._xmouse-this._x;
	var distancey = _root._ymouse-this._y;
	if (distancex>0) {
		signx = -1;
	} else {
		signx = 1;
	}
	if (distancey>0) {
		signy = -1;
	} else {
		signy = 1;
	}
	var forcex = 0;
	var forcey = 0;
	var distance = (distancex*distancex)+(distancey*distancey);
	if (distance<maxd) {
		force = (-1*a*distance)+power;
		forcex = (distancex*distancex)/distance*signx*force;
		forcey = (distancey*distancey)/distance*signy*force;
	}
	var speedx = ((speedx*friction)+(this.basex-this._x)*ratio)+forcex;
	var speedy = ((speedy*friction)+(this.basey-this._y)*ratio)+forcey;
	this._x = this._x+speedx;
	this._y = this._y+speedy;
};
[COLOR="#ff0000"]with[/COLOR] (mask) {
	mask.onLoad = function() {
		basex = _x;
		basey = _y;
	};
}
[COLOR="#ff0000"]with[/COLOR] (mask1) {
	mask1.onLoad = function() {
		basex = _x;
		basey = _y;
	};
}
[COLOR="#ff0000"]with[/COLOR](mask2){
	mask2.onLoad = function(){
		basex = _x;
		basey = _y;
	};
}
[COLOR="Red"]with[/COLOR](mask3){
	mask3.onLoad = function(){
		basex = _x;
		basey = _y;
	};
}

onEnterFrame = function () {
	mask.repel();
	mask1.repel();
	mask2.repel();
	mask3.repel();
	b1._x = mask._x
	b1._y = mask._y
	b2._x = mask1._x
	b2._y = mask1._y
	b3._x = mask2._x
	b3._y = mask2._y
	b4._x = mask3._x
	b4._y = mask3._y
};
stop();