Interface disappears after talking to a girl (and game resets, but you already know it)

Lathlaer

Ok, so here is the problem - during the Hexxat's quest (library) I had to load a quicksaved game. Imagine my surprise when my loaded game put my party where it should be but the areas I discovered so far were covered black (as if not visited yet).

So I shrugged this problem off and continued playing. After escaping the tomb, literally every area I have been to appeared as unvisited. And some of the quests looked like undone. When I went out of Copper Coronet I was approached by Galean and he just made his deal (20k for rescuing Imoen). Obviously I spoke to him about it a long time ago. Most of the monsters resumed their previous positions (I have 2 copies of Namara +2 and Daystar).

Now, that isn't the problem. I can work with this because there isn't that much I have done so far.

My main problem is that after completing Neera's quest, when I'm in the Bridge district, two things happen:

1) Lanneth appears alive and well, although she just stands there and does nothing, literally waiting to be killed
2) a small girl talkes about her mother and hairband. I also have a distinct feeling that she should not be there

The major problem is, after talking to her, my interface disappears. I can still select my party, I can pause and do everything, but if I want to see battle log or the portraits or the options, I have to hit pause.

Happened to anyone? Possible solutions? Perhaps I can somehow go around this by setting this small quest as already done so the girl doesn't talk to me? (the problem appears when she starts conversation)

EDIT: So far I have found a brute force solution: I threw a fireball and killed the girl. I'm curious if someone has a better one.