How can i continue duplicateMovieclip(ex.15 times) with one missing instance(ex.10)

while(z <= rensize) {
var ren = this[“numere_” +z];
ren._x = xren;
ren._y = yren;
xren = xren + ren._width-70 ;
z ++ ;
}

more exactly can i make a duplicatemovieclip that finally loks like this:

home
more
old

nice
keep

there is a missing element.And all is made by duplicate and distances.
i want to keep the distances but in the missing case i want to not activate the button and keep the distance…

thanx for anybody’s help