Can't resize images loaded from MovieClipLoader

I’ve got a gallery that loads images in using MovieClipLoader. Unfortunately once the images are loaded they don’t seem to want to be resized.

I’ve added an empty MC to the stage for each one and loaded the image in, then I try to resize it to fit the screen. Tracing the size after the onLoadComplete event returns 0 and changing the size makes the clips disappear from the screen.

Anyne have any ideas why?