http://www.creationkit.com/Creating_a_Merchant

I followed that tutorial, to the letter as far as I know on a duplicate of a flame atronach (removed daedra faction, increased happiness but nothing further).
I can't interact with the creature. It has no scripts attached so I can't understand why it would not behave as any other NPC. (I gave it a maledunmer voice btw as said in the tutorial).

What am I doing wrong?

maybe just try to copy any other NPC and change its model to flame atronach model?

Ow wait, I've solved this 2 days ago.
Changing the model might have worked (but wouldn't that involve a lot of settings for everything?)

THe solution was simpler: WHen I changed the race to flameatronach I didn't know that a race is actually an entire object with a huge form attached. It appears "creature" races have a race where the "allow PC dialogue" button is NOT checked.
So after copying the flameatronachrace file and renaming it and ticking that box that allows dialogue everything is ok.