First thing you need to know how the spa files act, every spa file have the same images but diferrent aplletes, just one pallet correspond to one image.*
*The last spa files have diferrent images.

1- Open the NSMB Editor with a Clean Rom
2- Go to the File Browser and open the the particle folder
3- Export yhe spa file you want
4- Open the MKDS Editor and open the spa file.
5- Look the images!!!

It's just that, remeber you can't edit just saw for now.
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Did you really have to edit a post of yours from 2 years ago? -,-

You know that also if you just edit a post, the thread comes at the top of the forum and will have a "+1 NEW" thingie next to it, right?


EDIT: Ah well, now we're bumping this thread anyway,

the *.spa file format isn't that complicated as many people here think. I've had a talk with  skawo a while ago, and he said he had managed to modify palettes of a *.spa file pretty easily by Hex editing. A *.spa file would basically be something like this: