how to group image and new background

[SocolikCardShop]

I have an image where i removed the background, then added a different background.  I would like to group the image and background, but it does not work when i select both, then click group.  i am trying to create and save this new image.  any suggestions would be appreciated.  

[Windy]

I just tried this and it worked fine for me, but in my case, my  backgrounds are always another image that I uploaded specifically to use as a background. When I try the same thing with a Zazzle provided background it does not work.