Yay, I get to be helpful for my 500th post.
Make sure your gfx are either .gif, .png, or .mng files. If they are .png or .mng, make sure they have color depth of 8-bit (256 colors). If you still can't get them to work, create .gifs and drag them onto the gif2mng.exe icon in your Graal directory; the exe should spit out a usable .png or .mng image.
And no, you may not use my tiles. Thank you for being interested in them.
