Important information about viewing images with green screen backgrounds

The online ordering system you will be viewing your images on allows for clients to choose their own backgrounds.  The program shows a rough estimation of what the photo will look like with a chosen background.  Due to this, it is not capable of differentiating between what is background, and what should remain foreground if the colors are similar.  All photos ordered will be processed in our computer program that allows us to define background and foreground, and is much more precise. 
Below is a sample of some issues you MAY see in the program on the left, and the differences in the finished product that you will receive when printed on the right.