Though I do find the choice of using Cinelerra to edit the video a bit odd. Apparently there was an update to the project less than a year ago but I have personally never even been able to even import a video without it crashing.

Using something like OpenShot, KDenLive or PiTiVi or even Blender only makes sense to me.

But Cinelerra obviously worked out for them; the productions are absolutely spectacular. Loved every bit of this one. The clearest explanation one could hope to get.