This is a known problem in Construct 2: you inserted the worldArray object to a layout, deleted that layout, and now you can't use the object.
When you insert an array an invisible instance is also added to the current layout. If you delete that layout the object then has no instances, so you can't store any data in it, but it still appears in events. You can tell this has happened because if you select worldArray in the project bar, it should have width, height and depth properties, but those properties do not appear. Your 'On array created' event will also not be running, because there is no array that gets created.
I'm afraid for now all you can do is replace the object, or tweak the project XML to add the array to another layout. We're aware of this problem - I'll see if I can get something in the next build to make this clearer and easier to work with.