ok that's the best i could come up with at the moment until someone els posts a better or an easier way.
basically this is very helpful for making low res stages without loosing the color quality due to the 256 colors conversion.
what i mean is low res stages will look much better with minimal color loss.
what you need is photoshop or any other software that has the slice, select and move tools
1-open you image then pick the slice tool
2-right click on the image and chose promote to user slice
3-adjust you slice dimensions or leave it automatic ---> up to you..you can do it in real time as well by dragging the borders
4-pick the selection tool---> the square one under the move tool in photoshop
5-select the outlines (borders) of your slice using the selection tool.
open up a new blank image then use the move tool to move your already selected slice to that blank image
6-corp if you must, convert to 256, save as pcx,
7-put the slices back together in the sff
done
repeat from step 4 for every slice
example
i hope to see some better looking stages