I had the exact same problem for a while. The way it was fixed for me was by a reinstall of Chameleon. In fact, it has happened more than once to me and it was always fixed by Chameleon reinstall. So, make sure you have the right Bios settings and your custom kexts are only the needed ones using Lion as your guide. Then reinstall Chameleon to the right partition using Chameleon Wizard and it will work.
my chameleon used that worked was 2.1 r2035