Thank you!
Well, not really. By that I mean, that there's no such variable, where you just enter the new size et voila! You can move the "A"s around as you please and they set roughly your upper limit. Then you'll have to make some minor adjustments in the code to set the lower limit.
If you want to add new rows, just add more "A"s to the stage, but don't forget to refresh the number of rows in the code.