Control movie clip duration with an external config file?

programming flash
1

I have a stage with a few different movie clips placed one on top of the other, in different layers, one frame per clip. One is a day time scene, one a night-time scene, one is raining, one is just cloudy. I want to be able to change the duration they run before switching to the next clip, or maybe even prevent it from appearing (maybe if duration is set to ‘0’?).

I want to be able to make any adjustements to the clip lengths by simply editing a text or XML file.

Here is how I’m controlling the clip length now, although I’m open to better ways.

function sunnydayFrame() {                
    nextFrame(); 
    clearInterval(myTimer); 
}
myTimer = setInterval(sunnydayFrame, 8000); // calls the function to advance frame after 8 seconds

The next frame is the same except it is function rainydayFrame () and it is myTimer2 and so forth.

Thanks for any help you can provide,