There's another series of videos that kind of document the design and construction process of the Marble Machine X. He opened up his design process to a collaborative group of engineers, and some of the things they came up with are pretty impressive. Most of them, I believe, are university students from all over Europe. It's kind of inspiring to watch.
They make good use of CAD, CNC milling, and 3D printing. It's more than a bit fascinating.