What is the best method to create an easy to use flash file that will allow
horizontal scaling with a fixed vertical size?

This will be for a blog header in a variable width design at
http://makelightreal.com

I have tried the basic stage properties and found
[b]StageScaleMode.NO_BORDER[/b] to be an ok solution, but I'm not sure what
will happen when I begin to drop active clips in on the stage. Will the stage
operate from a fixed point or how will the clips orient to the stage as it
expands?

My understanding of actionscript is just enough to hack pieces of what I need
together: but if you could enlighten me with the most basic understanding of
which method would work best for me I'd apprecate it. I also have this method
to alter the background (as a clip):
[Q]Stage.addListener(ecout);
// function which replaces all the elements with the new values
slide = function () {
photo_mc._x = 0;
photo_mc._y = 0;
photo_mc._width = Stage.width;
photo_mc._height = Stage.width/rapp;
if (photo_mc._height<Stage.height) {
photo_mc._height = Stage.height;
photo_mc._width = Stage.height*rapp;
}
};
slide()[/Q]

Should I just alter the variables there to lock the stage height?

Thanks for your time in answering.

When you export your movie you can select the scaling options for width and height.
Try selecting one but not the other.

Cheers,
Gorka