I suggest you get the Image Mod (linked in my sig) and add your images to be compatible with it, and submit them to the mod. Also, feel free to use any images from it that are appropriate.
You can add new lines to the components.bmp file. The mini is a 36x36 size reduction of the portrait, placed so it matches up to the number of the comp bmp. The Image Mod has a number scale on the side for ease of reference. Basically, the numbering starts in the top right corner, and increments one with each pic to the right, then goes to the next row.