Can I use double or triple layer corrugated?

Technically, yes but we advise strongly against it if you are using it for boxes. The reason is that the lengths of all cuts are calculated taking the thickness of the corrugated cardboard in account. When using a single layer, the cardboard will bend in the middle of its thickness. With multilayer corrugated cardboard that depends on every layer. If you think the corrugated cardboard at hand is too thin to survive transport, consider making a 1-click-Matryoshka.