Gaijin-Eyes has produced some tutorials that are hosted on BorisTV.
Many are about Avid FX for Avid Media Composer.
However, from Boris RED 5.5, instructions for using Avid FX/Boris RED apply equally well to any NLE using either as a plug-in.
Newer Tutorials on BorisTV refer only to Boris RED but can be applied to Avid FX too.

The link to Boris TV is here: BORIS TV