How to make/replace a PORTRAIT ?

The tutorial from Nba Live 2005 about this isn't enough.
When I make a portrait, picture shows good, but there is ALWAYS fuc*ing background (white, black...)
How to remove it, and how to make a transparent picture ???
I use Paint Shop Pro 7...
I need to open the BIG file first, and then the fsh file of some player, then to export it with fshX tool, and save the picture as bmp.
I open that picture in Paint Pro 7, and open the picture which I want to replace with the old one..
What I have to do then ?
How to make it transparent ?
Pls...help

I don't think there is a way to do it in paint shop.

You have to save it as a .png but paint shop pro wont work if you save it as a .png. You have t use photoshop. I still cant get it to work in photoshop. I havent tried making portaits in photoshop though.