Not array inventory.

Hello, i have a problem, i'm trying to make a non-array inventory and i have got a problem that i didn't expected to have. I made an event where when you click item, it should appear in square with id(variable as id) 1, then if it's used(another var) it should use another one, and there the problem began. I made a text to check locked and unlocked slots, when i pick up an item, item changes position and layout, then, when i try to pick up another one, happens nothing. I tried many things such like:

Event: ON 'item' clicked

Sub-events: Locked slot isn't 0, id = 1...change layout and position of 'item' and change var lock = 1(locked)

Sub-sub event: (is the same but with id 2)

I figured it out, i think i made a great inventory system, easy and 1 slot = 1 event :D

I have only one question: When items are overlapping themselves and i press on them, one only goes to eq and one destroys, how can i prevent this?