Hmm I haven't much experience with Paint Shop Pro or Paint.Net either, but I'll look into it. Are you familiar with GIMP? It's capable of opening PSD, but I'll require to rasterize the layer blending options and also forward the font to you.
If you aren't familiar with it, I'll see what I can do. Most likely I'll hand you a transparent PNG or a format with native Paint Shop Pro support. Gimme some time.
Also, in Photoshop, you can add a background image by going to the bottom-most layer (actually, the lowest layer, but above the Background layer; you can create an empty one there). Simply drag and drop an image from your folder onto Photoshop, and drag the layer onto the lowest level.