I find if you are importing a background into poser, it's best to change the pose window to the same size as the image you are importing. So for example if you are using a 1024x768 background, make your pose room window that same size. You can also try putting the background on a square in the material room and use it as a prop so that you can move it around and stuff in the pose room. However, I've tried and can't get it to work very well for me. It's the hole distance, size and placement thing.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi