WC + WC produce an F1
F1 + F1 produce an F2
WC + F2 produce an F1
F1+F2 produce an F2
The filial system is based on the distance from wild caught blood
The CG system is an unofficial system adopted by us hobbyists to communicate how many captive generations are involved. This is very important for us chameleon breeders as if you get a gorgeous WC panther chameleon and mate it with a female which has 9 captive generations of bloodlines behind her the offspring would be F1 just as if you mated that male with an unproven WC female. But an F1/CG10 baby Ambilobe is the best of WC blood mixed with proven and refined captive bred blood. An F1/CG0 baby Ambilobe could be a mixed baby depending on the labelling accuracy coming from Madagascar. The CG designation is unofficial hobbyist lingo and is not adopted by everyone and many wouldn't know what it is. But the ones that do use it are giving you much more valuable information about the genetics you are getting.