1. In 0:49 what is that book dimension?
It's one of those areas that are outside the World's Parameters, Ovan created the mark there in G.U +, as for GU unsure if he does it there too.[/quote]
2. In 1:07 who is that person? Is he Yata?
Yes that is Yata, either infected with AIDA, or encounter with Zenith or Awakening his Avatar
3. In 1:09 who is that person? I've heard its someone called Enia or something. Who is she?
Eina is suppose to be the ultimate A.I, it's still a bit rumored, however it's believed her voice actor will be the same as Aura's voice actor.
4. In 1:30 is that Cubia? How did Cubia come back? What is he doing in G.U?
Unknown for now, 1:30 is a high high probability that this is Cubia, something created him, rather it's an anti-existence or another cause, unknown.
5. How exactly did Haseo get Xth Form. Based on the trailer it appeered that when he got infected it happened. Why?
2 Ways (Speculation)
A. When he breaks out of AIDA his Xth form is created
B. When he infected by AIDA he is forced datadrained, which sends him to an odd wasteland, there hackers in Netslum (The city in the sky of that wasteland) take him to what appears to be like an operation room, and hack his character to save Haseo, as well as the real player.
6. How did Haseo get the Azure Knights into his party?
It's known as a "Decisive Battle" at the Cathedral, obviously either a program, or Azure Knight's subconscious causes this, or just an extra thing in the game.
7. In 2.:48, when Haseo is summoning his newest version of Skeith it appears that a girl's voice is talking with him. Is it Atoli or Shino?
Besides Kuhn, Atoli, and Endrance calling out, Shino is talking as a narrator.
8. In 3.:30 it shows Shino? How did she come back?
This is unsure of, however we can take this cutscene as a "Cloud" moment, If you watched Advent Children you'll understand. Also this can be counted as the ifnal episode of Root's moment as well.
Basically it's an imagination Haseo has created within his mind, yet it's not really an imagination. You can sorta call it a "spirit" of Shino talking to Haseo's mind. It's normally used for drama purposes.