Application with background image and several images on top of it

[Svein Erik]

I'm developing an application in C#.NET 2005.

The app is going to have an image with a specific size, let's say 800x600
px, this is a map of a go-cart lane. And on top of this image i'm going to
place small images with traffic lights.

I have the code for changing the images according to which light should show
in the traffic-lights, what I don't know is what the best way to place the
main image (map) and the traffic light images on top of the main image is..

Example:
A main image with the map is 800x600 px, and I want to place 5 traffic light
images on top of the main image. I will have 3 different traffic light
images, one showing green, one showing yellow, and one showing red.
What is the best way to make this, when keeping in mind that it may be 5
different versions with different main image (map), and different numbers of
traffic lights in each version.

Thanks in advance!