I really liked the idea of this mod, as it made character creation and gameplay more diverse (even if a bit too easy at times), so I decided to give it a try about 2 weeks ago.
Unfortunately my progress was halted after clearing out Kresselack's Tomb, as Lysan never spawned in the cave. I started a new game a few days later and got to the point again where I was supposed to meet he priestess, but she was nowhere to be found this time either.
If anyone could provide me with a solution to this bug I'd really appreciate it.
If you have not actually agreed to kill her, ie. if you said you would 'think about it', then she won't show up. You MUST say you'll dispose of her to Kresselack, who will then tell you she's in the vale.