What happens when you say you can't boot Snow anymore? Does it not show in Chameleon's GUI? or does it KP when you select it from Chameleon?
Can you type diskutil list in to the Terminal and post the result here, along with details of where you have installed Chameleon. Also can you try booting in Verbose mode (-v) and post a screenshot of when it fails?
For reference, this is my folder structure for Chameleon: