I have my criticism on the game, but some of these seem odd to me:
Zhent:
Why wouldn't the Zhentarim mine the bottom? They already have supplies close to the upstairs area, wouldn't want to damage those. I think this is fine.
Last Light:
Timings working out like that is just something that happens in every narrative. Could as well ask how Frodo in the novel just randomly left right the moment before the Black Riders arrive. If you want a rationale, the timing of the attack makes sense since Marcus was able to observe Isobel on the balcony, so he knows exactly where she is. It would have been awkward attacking the place and look around for her since she is just on the loo.
