I have to ditto on the need to know more about what you want to create.

Our Vintyri (TM) Project is at present writing a free and open tutorial (PDF) that will deal with making raster (bitmap) symbols with Fractal Mapper (TM) 8 and then adding transparency with Paint.NET. There is no release date yet, but I expect it to be available sometime in autumn. You might want to check our homepage after summer's over.