I have experience with the Cs creating races and custom npc, so I have with Wrye Bash and OBMM.
All right in the save, she looks gorgeous, all right in the CS, she looks fine.
But when I talk to her... the magic goes away... with that horse-smile like!
I don't understand why when I talt to her she forces that horrible smile. She smiles correctly in the ess, and so she looks in the CS.
I lowered her disposition a bit trying to solve this, and closed her mouth all that I could in the save before copying the face to my faceslibrary.esp.
http://i217.photobucket.com/albums/cc189/Zimnel_Redoran/oblivion%20varias/TESConstructionSet2010-07-2921-07-56-74.jpg
http://i217.photobucket.com/albums/cc189/Zimnel_Redoran/oblivion%20varias/Oblivion2010-07-3000-44-52-59.jpg
http://i217.photobucket.com/albums/cc189/Zimnel_Redoran/oblivion%20varias/Oblivion2010-07-3001-23-06-28.jpg
If anyone has any clue of this strange behaviour, it all points to the head animation, but I cant't be 100% sure of that.
I planned to release her as Cm Triss in a mod that adds her as a companion in Chorrol mages guild, but first I have to solve this.