Potential System, halp

So let me see if I understand this. Please, bear with me. xD

1) You scroll a clean equip with a 70/90% potential scroll to make it unidentified. Does it have to be clean? Does it take a slot away from the item?
Does not have to be clean, it will not take a slot.
2) You use the magnifying glass on an item that is unidentified. It gives stats randomly.

2a) You can reset it using a CS item until you get what you want.

3) You scroll the equip normally how you would after you get the desired stats. So you scroll after you identify it?
[B]You can scroll whenever you want.[/B]
4) You use the star system (forget the name) to make it better after you get to 0 slots left. How exactly does this make it better, what can it do to it?
This one I'm not too sure of.
Sorry if these were answered already but I didn't see them before so I figured I'd ask.

Edit: Also, I'm guessing items that are already scrolled can't be scrolled with a potential scroll which would make pretty much any gear we have at the moment inferior once this comes out?
You can scroll pre-scrolled items.

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