I cannot understand how this pink matrix appears in the block diagram. (Copy/paste from the examples we tested it's not working properly. I must do myself your circuit for 3 combo boxes)
Hi treadagon, if you mean how to create an array constant, then go to the array section and select an empty array. Insert a constant of the data type you want into it and you have your array. With right click on it you can add or remove a dimension.