Strange thing. When player is in the city, closing character sheet always moves player into World Map. Seems that this works for every type of non-wilderness location (I check village and Ankheg Nest).
To make matters worse, this 'action' takes turn!
So, I checked my stats, close charsheet, and... was immediately attacked by enemy. I had only few HPs, and my character died :<
Bug: Error drawing Ankheg
One more thing. Probably I mentioned it earlier, but I think you didn't answer this question. This time I'm not sure, this is only my memory, but maybe you should check it? Anyway, Shephard Dagarig who gives Ankheg quest tells about 'grandfather's magical boots' as a reward, and if I remember correctly Shephard gives magical book instead of boots...
Do you remember how I wrote about covering some tiles (items on floor) by enemies, when area was out of FOV? Yet another clue. I was on first special level in temple (5 level deep) and I noticed that sometimes floor tile is replaced by empty tile (black space, without dot); I think this was caused by presence of monster.