Metatron wrote:

1st A. Yes, Same as Equipment, Only IM weapons cannot be inserted with diamonds.
2nd A. You cannot insert another diamond to an inserted piece of Equipment.
3rd A. Cupid is System that the operators that give him the instructions what to say within x amount of times don't know English very well, Those are the Live Support Operators..
4th & 5th A. No, Alchemy is risky, It will never be 100% even with maxed Superior/Junior, I use Maxed Superior myself and my Lvl 7 one does better in some formulas for me.

Hope it helps ^^

Oh... for the 5th one,
It's pretty disappointing since I'm on the way to making my superior's lvl 30lvs. I'm at lv21, soon will be 22.
And It really sucks when you hear that still some formulas give out better results with low lv alchemy. What's the point :(