The dark lines around transparent sprites is a very common glitch. I believe there is code in the archives that deals with that.
There is a mask and an alpha flag. Masked textures are drawn without any black pixels. (RGB=0,0,0) About alpha, I think I've read that blitz can only handle 2 alpha steps, on and off, but I'm not sure.
There is a mask and an alpha flag. Masked textures are drawn without any black pixels. (RGB=0,0,0) About alpha, I think I've read that blitz can only handle 2 alpha steps, on and off, but I'm not sure.