Edit morph in animation mode

mr.jesps_c46584723b

Hi,

I'm trying to use Carrara 8.1.1.12 (non pro) to create/edit a morph in order to fix poke throughs, like is done is this tutorial:
https://www.youtube.com/watch?v=dXZvs716Ov8
However, when I enter "animation mode" in "edit vertex object" the 'edit' button (a little pencil) disappears.

Is there some obvious setting I'm missing? Or does it have something to do with the models? Here I'm using Victoria 4 and the sports-bra from Daz, but it's the same with other models.

Cheers