You can perform this convoluted method OR "just use a simple Outline font" which can be freely downloaded.

  Already with the default overlay
(Normal) the result is not exactly the same as in the tutorial. For
example, the outline of the letters is all white while in the tutorial
there are plays of light and shadows that make it three-dimensional.
But the worst comes when I set the center track to "Multiply": a
completely wrong color comes out!

 

 But I have growing suspection we really do some calculations differently, may be in more widespread/standard way but not like original Cin worked.

 

Agreed.  CinGG does some things differently as well as calculations.  That does not make them wrong.