1. Yes, you get ur rune back
2. You drop items if u are PK lvl 4 or higher (red nickname)
3. U add lvl 1 to lvl 1 rune to get lvl 2, 2x lvl 2 to get lvl 3 etc. If u fail u lose one of them
4. Cant rly tell cuz im not spoiling
5. There is special slot in ur inventory
Good luck