1. Create 2 movie, name it to red.swi and blue.swi, export each movie to .swf format
2. For the main movie, create new movie with the same size with the other 2 movie to load. i use 2 button to load the movie here
3. let get to the script, click on the firts button (red button) . open the Script panel, Add Script-Movie Control- Load Unload Level- Load Movie [num]

4. that's it, follow the first steep for secaond button


Example | Download .SWI