Here's my solution:
1. Create a mainmovie.gla file, including Scene 1, and also including the Sene A to Scene E;
2. Create a basemovie.gla file, and add Button A to Button E respectively into the Scene, which will be pressed and help jumping into the corresponding scene.
3. Add action script for the Release event of each button. Take Button A as an example. You can add the following action script like:
_level1.unloadMovie();//unload the basemovie.swf file from the main movie;
_level0.gotoAndPlay("Scene A");//force it to jump to the Scene A in the main movie;
4. Add the following action for the event "Enter Scene" of Scene 1:
loadMovieNum("basemovie.swf",1);//load basemovie.swf into the main movie, and set the deep value as level 1:
5. Add stop(); to the "Enter Scene" event of Scene A to Scene E respectively, thus you can enter each scene by clicking the corresponding button.