>>4 speaks of kosher salt, sea salt is of the same texture but is more of a kind of salt used by chefs with porsches.

To make different types of flavors to the popcorn is quite a CORNy idea ^^ you have to essentialy marinate the kernels before hand and leave to dry, or there are some popcorn shops out there that will sell flavoring powder that is ground extremely fine.

Now onto Kettle Corn...i have no idea how it works, ask a carny next time you see one making kettle corn.