Sprite objects not sticking to z-order

I'm having trouble with sprites not staying behind other sprites on relaod of the layout.

<img src="http://i.imgur.com/LpUPQ.jpg" border="0" />

On the left is what it is supposed to be, and what happens upon the FIRST instance of loading the scene. When the scene is reset however, the second image occurs.

Any help would be greatly appreciated! Thanks!

Have you used different layers for that?

If you use different layers behind others you can put the sprites at your taste.

scirra.com/manual/42/layers-bar

They're all on the same layer. Guess that will have to change!

I just wonder why it seems to work fine once and then never again :)