All things translucent. Jade, Marble, Milk, Wax, etc
Yes, you can run both versions in parallel if you bought Cheetah3D via my webpage. If you bought Cheetah3D via the Mac App Store it is a little bit more complicated since the MAS overwrite the old version. So you first have to bring the old version at a save place where the MAS installer can't overwrite it.
Bye
Martin