I need to add values to an array as long as they show up in the game, but not at specific X,Y, I just need them to be added at the bottom of the "list" (actually I want the array to behave as a multiple global list object). Those values must be stored in one of the four columns - in this little picture I've labeled them with string titles but I don't necessarily need them to be "keys" of the Associative Array, those could be just numeric X 1, 2, 3, 4, so maybe the whole thing can be done with the normal Array Object.
Basically, every "column" must behave as an independent list. I need to add values to the bottom of a specific X column, whatever the last Y "coordinate" is. If I use the action "Add 1 to Y dimension index" a new line is added to the bottom of the whole array "grid", not only to one column. How can I tell it to "search for the bottom value of a specific X column and then, if exists and is empty, store a value OR first add a new line and then store the value" ?