Shaoram
Currently, mod works
only with .act files. Renaming .gpl to .act will break palette. You need to convert .gpl to .act, use this converter for it
You must be registered to see the links
I have no experience with GIMP, but recommend to use Photoshop, any version of it, that can work in Indexed mode (powerful color change tool, but limited .act management), Fighter Factory (Advanced Palette Manager in it) (very good .act management) or PalEdit (no preview) to change colors in .act. All palettes that in current game build is done with Photoshop CC and Fighter Factory Studio.
Edit: Thanks to Teravisor, mod can now read .txt palettes
wait for update. Just save that GIMP palettes by right click with
Export as >
Text file. Paths is same as with .act paths in .json