I don't why I'm getting spammed with the same questions when I logged in earlier, but whatever I'll just answer here since its just a pain shifting from pm to pm.
Shapeshifting Scrolls
1. If you ask me if these scrolls are worth exchanging or not I'd say their both, because its only weapons getting their own costume.
2. These aren't actual weapons like the ones you need to smith.
Event Magatamas
I only got 1 of the 3 recipes available from the exchange shop, so I don't know if you need the snow mag 1st to make the 2nd mag, then you need the 2nd mag to make the 3rd.
Also the achievement says craft the frozen hell mag when there's no recipe for it(It maybe in the clear rewards though I'm not sure), but I think the only way to get this mag is to finish the 3rd dungeon 50 times.
I've only answered the same questions, so about the remaining ones you'll just have to ask the other players for it, since I'm not really online for that long.