Do not downshift at all if you can help it. Yeah that noise sounds great b ut your tranny parts are saying WTF over?!!
Brakes are cheaper to replace than transmission parts.
As to what you broke, I dunno maybe pilot bearing or tob not liking you. It could also be something else.
Oh god that's not good! Sounds like seized TOB, or broken clutch fork/pivot ball. If lots of smoke poured out, then I would guess the clutch broke too. Also, it could be the springs in the clutch, sometimes they pop out and wreak havoc!