3. When loaded with black powder, do the cartridges retain their smokeless designation or do we call them something else? The .38, .38 LC, .357 designation seems to loose the distinctness of its meaning when we are changing bullet weight, bullet type and powder charge.
As long as your cartridge is .32 caliber or larger, SASS doesn't really care, other than safety rules. You are welcome to use black powder loads in .357 magnum cases even in the frontier cartridge class where black powder must be used.
SASS is more about "the spirit of the game" than it is about absolute historical correctness. It's not the NSSA or the Revolutionary War Re-enactors.