Using the CENA plug-in

This one should be created automatically when starting Brainstorm...
What do you see in this .brainstorm folder?
What you get if you execute "bst_get('UserProcessDir')" from the Matlab command window (while Brainstorm is open)?

I do have the pathway brainstorm3 > toolbox > process > functions; should the CENA files go somewhere in there? Most of the existing brainstorm process files are in the 'functions' folder and a few are in the 'process' folder.

Don't add anything to this folder, or it would go away at the next Brainstorm update.

Does the process_cena_pub_src folder go in the same place? And as a complete folder, or should the contents be extracted first?

This I don't know.
@georgemonteleone ?