1) 1 or 2 screens further of Bone village. Kjata materia is in motion, (dis)appearing on the left and the right part of the screen behind the foiliage.

2) 1500 gil I think = guess

3) the Nibelheim Flashback theme?

4) Can be 2 situations I guess: 1st situation is the Nibelheim Reactor where Sephy has a go at him with his sword and 2nd situation where Zack goes together with Cloud to Midgar and Zack dies of his wounds.