I created this conversion guide 1-2 years ago that will clarify many of your questions:
http://www.mediafire.com/view/umm5vkq0jjt91v6/converting_CHD_CF_Guide_2.pdf
Basically the 3rd track of a GDROM usually contains a big BIN file, which must be decrypted.
http://www.mediafire.com/view/umm5vkq0jjt91v6/converting_CHD_CF_Guide_2.pdf
Basically the 3rd track of a GDROM usually contains a big BIN file, which must be decrypted.