afaik, there's no way to convert a grf back to a png or bmp file. What you could try doing is taking a screenshot of a skin using an emulator such as melonDS, and then take the graphics from that screenshot.Hey Robz, is there any way to get original png/bmp files for the themes listed on the skin repo? Or at least a few of the default ones; at some point I had copies like this, because I have a few I edited, but now when I download the skins they only have .grf files in the grf folder. I used to love how easy TWMenu was so easy to modify. Would there possibly be a way to convert them back?
Also, I'd say modifying TWLMenu++ skins is still easy (maybe easier?), because you can create a theme using an example one here, and can contain only bmp/png without the need to convert to grf.