PROBLEM WITH SCROLLER AND FEW MOVIECLIP

I HAVE 10 MOVIECLIP AND I PUT SCROLLER FOR SCROLLING 10 MOVIECLIP,BUT ONLY 5 MOVIECLIP IS COMIN AND SCROLLER IS WORKING.

WHEN I M WRITTING THIS

thumbnail_group.addChild(flashmo_tn_mc); IN CODE THEN EVERY TIME THE VALUE OF

main_menu.numChildren IS DECREASING.....LIKE main_menu.numChildren=10

main_menu.numChildren=9

main_menu.numChildren=8

main_menu.numChildren=7

main_menu.numChildren=6

AND ALSO IT SI PRINTING ONLLY EVEN NUMBER MOVIECLIP............AND WHEN I M REMOVING

thumbnail_group.addChild(flashmo_tn_mc);

ALL 10 MOVIECLIP IS COMING BUT SCROLLER IS NOT WORKING....

PLEASE GIVE ME SOME IDEA.............

for( i1 = 0; i1 < main_menu.numChildren; i1++ )
{
 trace("children number="+main_menu.numChildren)
 flashmo_tn_mc = MovieClip(main_menu.getChildAt(i1) );
  thumbnail_group.addChild(flashmo_tn_mc);
 Tweener.addTween( flashmo_tn_mc, {  x:300,y:20+i1*100, alpha: 1, time: 0.6, 
      delay: 0.12 
* i, transition: "easeInSine", 
      onComplete: set_dragger, 
onCompleteParams:[i1] } );
  Tweener.addTween( flashmo_tn_mc,  { alpha: 1, 
scaleX: 1, scaleY: 1,
        time: 0.8, transition: "easeOut",
      
onComplete: set_dragger, onCompleteParams:[i1] } );
 /*
 Tweener.addTween( 
mc, { scaleX: 0.6, scaleY: 0.6, time: 0.8,
      delay: 0.08 * i1, 
transition: "easeOutBack" } 
);*/
 
 flashmo_tn_mc.flashmo_click_area.addEventListener( 
Event.ENTER_FRAME, btn_enter 
);
 flashmo_tn_mc.flashmo_click_area.addEventListener( MouseEvent.ROLL_OVER, 
btn_over );
 flashmo_tn_mc.flashmo_click_area.addEventListener( 
MouseEvent.ROLL_OUT, btn_out 
);
 flashmo_tn_mc.flashmo_click_area.addEventListener( MouseEvent.CLICK, 
btn_click );
 trace("down")
}