Paint Shop Pro :: X4 - PNG Graphic Disappears When Imported

I create a graphic in Corel Draw X4 and export it as a .png file. To test what it will look like when put on top of a black background, I also make a large black square and export it as a .png. I then open the black background in Corel Photopaint and then import the graphic into the background image. A siloutte of it shows up with the marque borders but the graphic itself (the colors and contents of the graphic don't). When combined with the black background it just disappears.