Item Bag System help needed

Hi guys, I am making a bag system, which allows the user to save several items.
I already did a mini-system, very simple called SBBS - Simple Bag Button System - which works through Dialog boxes and buttons and stores up to 12 items. The system works just fine, and is bug free as far as I know, however I didn't optimize the code to increase performance.
Anyway, it uses a simple Item Array that stores the items.

This new system I am making is also for a campaign. The leader of the campaign needs a bag system hard, and I decided to create SBBS while he is in holidays to surprise him. However, he has become my friend and I believe the project needs more, deserves more.

So When I was searching in wc3 database I found a system made by Toadcop:
http://www.wc3campaigns.net/showthread.php?t=91163

What I want is a lot simpler. I don't need all that stuff.
I just need to create a window when the hero uses the item (ability).
In that window the items in the Item Array will be displayed in a box, and the user iventory will be available in another box. I just need to make the change of items possible between boxes.

I saw how he created the window, using units and destructibles, but I make no idea how he creates the image of the item in each square of the box and his gride system is complex for me.

I will soon post my SBBS and an image of what I pretend. Please, does some one has enough experience in this stuff to help me ??

It doesn't need to be MUI, it is ok as long as it works and it bug free.
However I also have some troubles, it can NOT use vJASS, only regular JASS, and the use of game cache is very restricted, if not prohibited (due saving items from 1 map to another).
Please, people who help will have credit and get +rep.

Update coming soon!

First, I am sorry for double post, please don't -rep me, I am trying hard to help the community as well.

Ok guys, Here is my SBBS system. This is a simple dialog box system. It is not it's final version yet, the code will still need many modifications to improve performance, but you guys will get the main idea.

About the new system, I would like it to have this interface:
The area above the "Inventory" board would be for the items description.
The "Blue Bags" are the slots in which you can have items. The gray slots are slots in which you can not have them.
The main idea is to change items from the hero's inventory into the big box on it's left, like when we change items from slots within the inventory.

Please I already know how to make the inner structure of the bag system with the array. I just need huge help on the interface, because it is something I never did before.

Can some one help me ??
Please note this is a challenge because:
- can ONLY use jASS
- use of GameCache is limited

But:
- It doesn't need to be MUI

Can any one give me some tips ??

EDIT EDIT EDIT

Ok guys, here is a better verison of SBBS.
Anyway, About the new system, I just can't find out how they use the units and doodads to build the interface. When I placed them in map, they were so small !!
Toadcop uses some camera trick and I just don't know how he does it ! Please help !

I will send PM to Toadcop soon .. maybe he can help =S

EDIT EDIT EDIT

Hey Guys. Here I present you all with the last optimized version of SBBS 1.0.
The system's structure was changed in order to be more configurable and to require less memory space.

Anyway, Can some one help me out it CBS ?

EDIT EDIT EDIT

Guys I have a problem with the cameras.
Currently when you zoom into something wc3 increases the XX plane and decreases the ZZ plane. However, I just want to zoom in by increasing the ZZ plane and I want to keep the XX plane the same. Can some one who understands of cameras help me with this ?
How do I fix it?