I am very keen to apply different palettes to the sprites posted in this thread:

http://mugenguild.com/forumx/index.php?topic=134052.0

However, despite being familiar with GIMP, and searching far and wide for a clear method, I am unable to apply a new palette.

For instance, when I attempt to apply one of these palettes to one of these sprites, the colors are always off, with bright green scattered throughout the image.

I imagine this is a simple matter for some.  If so, please let me know how I can accomplish this.  Thanks.