Load external .swf problem / and setInterval?

Hi all.

i have an empty MC (Holder1) which i managed to load few external swf movies ( pic01, pic02… and so on) by clicking different thumbnail buttons
(btn01, btn02… and so on). After the first swf has loaded into MC Holder1,
by click “btn02”, it unloads “pic01” and loads pic02 into Holder1 simultaneously, since all of them are loaded into the same empty MC. Everything is fine till now if I wanted it this way.

but, I’d like the “pic01” to fade out, before “pic02” fade in. So I tried
this AS on each buttons. On “btn01” it says:

 
on (release) {
 if (_root.holder1._framesLoaded == _root.holder1._totalframes) {
  _root.holder1.gotoAndPlay("Out");
// fade out whatever loaded already
 }
}

and now i want to load “pic02”, i used the following AS and i know it won’t
work at all :

on (release) {
 _root.holder1.loadMovie("pic02.swf");
}

i am thinking of use sth like setInterval: to delay the loadMovie action
few seconds after the gotoAndPlay(“Out”) is called. Am I on the right direction? and if yes, how to write the AS using setInterval? And if not, what should I do?

Thanks in advance.