hi, I'm new to NGUI. I've just bought NGUI 8hours ago (and 1month exp in unity

)
I want to make UI for weapon shop. It's a vertical scrollview on left side, and the weapon preview on right side.
So, for practice I want to clone example7 but make it vertical.
It goes well when I use bunch of sprites only. then I want to group them in an object.
But I got trouble here... its example7's hierarchy

the "item0"... that's just an empty "trigger" GameObject right? or not?
I tried to create GameObject (isTrigger), and highlight it. then from NGUI > create > anything (sprite/tex/label) it won't fit the gameObject I created.
Its like the created sprite fills the entire world, almost 10x panel size (even it's just a 32x32).
below is a screenshot. The white box is a scrollview thats filled with a GIANT sprite that I create inside GameObject.

and you could see the little Xbox "A" sprite in game window. That I create outside gameObject (highlighting nothing, then NGUI>Create), and then drag it to gameObject.
It's been 4 hours since I got this trouble and looking for solutions. but maybe i'll just ask here

and like I said I just know NGUI last night. so don't be so rude X)