external image load/unload with button in MC

[hsarbaz]

I'm trying to create a movie clip which contains the background image and has thumbnails which change the image once you click on it.

Whats the best way to code this?

I'm having trouble with the depth.

addChildAt(imageName, o)

that works for the first image but how do i unload the image before going to next frame to load the new image when the corresponding thumbnail is selected?

thanks!