Few problems

[anthony]

1..
ALl GIF images are indexed images. They all contain a limited 256 maximum (must be a power of 2) 8bit RGB color table, no transparency.

If transparency is wanted, one color index is used to represent a single transparent color. Can be any color, uncluding a duplice of another color in the color table.

2. Naturally it isn't a direct color image, only a limited color index table image.
Convert the GIF to a RGB image before attempting to modify.

This is not a IM problem however.

I'll leave 3. to someone else. I suggest you publish it on the users forum.