Issue with expressions in Source SDK Faceposer

I have set my scene in faceposer to include smiling. And my loaded model smiles when I play my scene in faceposer, but when I copy the scene and sound file to Garry’s Mod, spawn an NPC, and use ‘NPC Scene’ to make the character act it out, his face remains neutral (i.e. no smile). The sound file plays, and he does the animation that I’ve set him to do, but no facial expressions. Would this have something to do with faceposing in Windows Vista?