If you are using Paint Shop Pro 4.12 (like me) to edit the graphics in USNF/ATF, you may have noticed one particularly irritating thing: PSP totally disregards palette indexes when you pick pen and background colors! What happens is that when you select palette index #255 (or 0xFF) for background, the program's puny excuse for intelligence goes: "Hey, the boss just picked a color with RGB values of 255 255 255! Since the palette has several entries with those RGB values, I will give him the first to match, so that I can use color #255 for something cool later!" The problem then arises: since the human eye can't see the difference between white and white, you will happily save the modified icon thinking it's all right, since the whole background is white. (That is, with RGB value 255 255 255.) The computer, however, uses only one thing to calculate which color should be transparent: The Palette index. In USNF/ATF, the color with palette index #255 (the LAST color of the palette) is considered transparent and your icon will have ugly white stripes around it! How to solve this? Easy! Once you've loaded the image into PSP (by using ATF/USNFTK's "edit image" button), double-click the background color box in the color toolbar. Then make sure the colors are listed by palette entry. Now, double click the last color (the one in the lower right corner, which has index #255 or 0xFF) and change the RGB values to something that is not matched by any other palette entry. (F.ex. 255 255 000) When saving the image, you may choose to reset color #255 to white again, or you may not! The game doesn't give a rat's ass what RGB values are located in palette entry #255, since it is transparent anyway!
I hope that made any sense to you now...