(https://youtu.be/WbVWXnRywhY)

This is Arch building Tool Volume-2 as the advanced model of the Volume-1. This node group is given as an example to show how to create this kind of arch pattern can be made by the duplication of the Arch Making node group.

With this node group, while you can play with the numbers and dimensions of brick blocks and the sizes of the mortar as same as Volume-1, now you can also change the tile order.

In Volume-2, the main goal is to keep brick blocks dimensions in a particular order. That's why : while each A, B and C brick blocks can not be modified separately, it is also added new math node groups and a switch node to control the orders automatically.

I hope this can be clear the understanding of that how the system works and help for your feature designs.

Thanks in advance.