Hello,
The 3D Coat part is really a quick one, just to create a model that will be exported. I tend to paint several things on the same layer (as in the video) which is obviousely not a good idea.
Also, this first video was done with 3D Coat 4.5 before I saw that 4.7 was out
I made a second one with 3D Coat 4.7 (and will follow new version annoucements, promised).
I found that the Octane Render workflow that is provided with the release does not work very well (or I did not use it properly) and made my own version.