Ouch.... why would anyone even write a tool to do that. It defeats the entire point of APNG format. As I said above, GIF format only contains 256 colors so converting such a horrible looking file to APNG is still going to leave you with 256 colors and a horrible looking file.

PNG can hold up to 24bit so the only way to get the best results from it are to make your graphics from scratch in 24bit resolution.

Cheers
james