I have good news and I have bad news. Good news is I got the werewolf mechanic to work!
http://i.imgur.com/EVCPxdc.png
Bad news. It seems we cannot use a custom skeleton, or you will get the result you see in the screenshot. I´ll probably have to rig it to the same skeleton we currently have in anim files. And that skeleton does not match the seducer model very well (wasn´t made with it in mind). The tongue is also going to be problematic.
Morrowind handles it like this. Anim files (no tail) -> argonian anim files (tail) -> werewolf animations. This way you can get a working tail for the wolf. We could use this to get a working tongue. However I suspect it may be a lot of work figuring this out. So do we maybe skip the tongue for now?
There´s also the option of forgetting the werewolf form. Just make her a creature, with tongue attack and her own skeleton. This is the easiest option here.