Jersey editing issues. Help needed.

[williams92]

I have tried to edit miami home and away short textures. Extracted .dds files with 2kx mod tool, then opened them with gimp, edited, tried to import texture back to .iff file, but the preview of texture looks all messed up. It would be nice if someone who knows how to edit jerseys with GIMP will add a short tutorial with detailed steps. I've tried to look in other threads but could not find any usefull info. Thx in advance.