Something more like this? I did this real quick in Photoshop, but if you've got layers and masks in PhotoPaint, the only rub is knocking out the white and dialing in your selection to eliminate any artifacts around the lower text (like you can faintly see in this low res copy) but still keep most of the flames. If your Corel file has the text separate, do the white knockout on the "art" part alone in PhotoPaint, then place it back into Corel.
To keep the white inside the art, duplicate the file, do the background delete on the bottom copy, then mask or erase the outside white and flame areas on the top copy, letting the softened flame edges on the bottom show.
You could also go into the bottom copy with the soft flame edges and add some harder edges to make the flames a bit more interesting, or to restore some of that which got lost in the initial white background "selection".
