I have create the “snow” effect with the linked tutorial, basically it manipulates the instance of an object on the canvas and calls the script in the actions on the animation load.
However, I cant get the generated snow to show behind any other objects on the canvas.
http://www.kirupa.com/developer/mx/snow.htm

You can see from the image the RedBox and the Border layers are above the SnowFlakes layer, I want them in front. How can I do that?
Flash’s DisplayList operates as an array with no empty values. If you have 10 different display objects on the display list, each will populate index position 0-9. 0 will occupy the lowest layer, on up to 9, which will appear to float over everything else.
So, to get your SnowFlakes layer under everything else, you need to make sure it is at index 0, or at least below everything else, in this case your redbox and border.
How are the “snowfake” objects added into the display list? Make sure that flakes are being added to the correct displayobject:
and that that object is on the right layer
I didn’t look at the tutorial, and you didn’t post any code, but I would guess that you are not adding the flakes to the SnowFlakeLayer correctly. Assuming everything else is layered correctly, that is your problem.