1. 

Start with the defaultplaceholder.fla

2. 

create a new file
menu insert/new symbol
create movie clip called "empty"
drag movie clip to where you want it name it placeholder1 or something
create a new layer in the timeline call it ACTIONS or something

put, for example,

placeholder1.loadMovie("title.swf");

into the first frame of the actions layer
do this for all your swf files but give each placeholder a different name.

You can also attach that code to a button. 

3.

http://321webliftoff.net