I'm not too sure if this is a bug, or just a mis-use of a GuiContainer. I am trying to make a gui open on an item's right click, with a couple extra custom slots. I got the player's inventory put into it, and decided to try it out, to make sure it was working so far, because I have not made a gui in the past. Everything seemed to be working, but when I try to click an Item, it doesn't let me pick it up, it just picks it up for a second, then puts it back. If I click an item that has another item in the slot above it, it will pick up the item from the slot above it, and empty both slots.
Thinking that maybe my code is conflicting with the gui somehow, I made a test mod with a gui, same thing.
I then decided to experiment a bit, so I added a few more slots (9 regular slots), and I was able to pick up items from my inventory, but not some of the 9 slots.
Thinking that maybe it has something to do with trying to use an item to call the gui, I made a block that would open the gui, and the exact same thing happened.
Can anyone please tell me if something is wrong with my code, or if this is just a bug? I have attached the source code for my test mod, with the 2 items, and 2 blocks