Fluorette

there's a number of reasons for the lack of activity among the general populace, but the more non-specific ones include: (1) the fact that you can't say or do a number of things here that you can do almost anywhere else; (2) the Nexon staff/mods presence (if even?); and (3) that forums all over the Internet in general have been seeing a decline for quite some time now.

Throughout the G21 it's referred to as the Elder's Sword (at least by Llywelyn) and a Greatsword (when you obtain the hitl).

On Wiki it actually comes up as Black Greatsword in the equipment list of the Elder.

Yes. Yes. Yes. I whole-heartedly agree each time this discussion is brought up.

Users have reported issues with having these quests on at the same time. Besides Duncan, Lassar is heavily involved in Chapter 1 quests, but she'll disappear from the school to appear in Sidhe Sneachta in an early G19 quest. Unless you clear that G19 quest first, you can't proceed with the C1 ones.
+ with G19 being a slightly more difficult Gen (at least for a newer, inexperienced player), it does not make sense to lump it in so early.

Another point someone mentioned a while back is that the level requirement in order to start G19/Chapter 6 isn't even enforced. You still receive it at level 19 (or whatever) instead of what's listed in the Chapter menu.

Something else, although this is way smaller: skipping Chapter 2 quests isn't an option - it's a quest that's also just handed to you early on, probably before you even realize what it actually does. It's necessary to talk to Kousai for other things (like certain skill quests), so unless you've read up on the Wiki first, you just have to deal with it. Chapter 2 probably isn't a big deal for most, but for someone who wants to play in order, knowing that you've hopped over to Chapter 3 just like that is a bit of an annoyance.

Also, we still haven't received the Masterpieces part 1 (allowing for the earlier chapters to be replyable) update for whatever reason when chapters 6 and 7 were recently made re-playable (Masterpieces part 2) in South Korea. BLEH.

One complaint I have seen for this game is that "it loves to not tell its story in order" which is technically not true, but the way to properly ensure that you can is far more effort than it should be. Let us play these things in sequential order. If players wanna skip gens/chapters, they can just talk to Duncan/use the chapter menu like they always could, just as you said.

No. It's a pass given by an event NPC, so naturally you just have to talk to the event NPC again to receive it.

Best I could find was this webpage from the Korean site. You'll have to click through the links (the pictures) at the top until you find the one that has "Dear. Milletian, Fantastic Melody (part 2)" (part 1 doesn't have all the tracks). On that page there's streaming services listed close to the bottom that have the digital OST.

There's two problems, though:
1. an account is required to download the album on all of the streaming services.
2. I only see .MP3s, no FLACs.