Normally trolls shouldn´t be able to research. However in one video on Youtube they are capable of this.
Is this normal or a FX bug? It might be due to Must Obey turned on, but maybe not. Normally the creatures groan when they are put in a room they don´t like(since some FX versions).
The uploader stated he uses 0.4.6u.
https://www.youtube.com/watch?v=0hN2hEMg9gg