One of the reasons I like dawnguard so much is the crossbows. I'm not entirely sure why, I just prefer them.
However, on my latest runthrough, I haven't been able to upgrade said crossbow. Sorine won't give me the option to ask her whether she needs any help. It appeared in the misc quests that I could go help her "improve the crossbow" but when I talk to her, there is no option.
This...svcks a lot. I've been through a good few hours, two levels, and a good few quests, including the tiresome process of joining the college of winterhold. Which doesn't actually require a lot of effort, it's just that after so many times, hearing people go on and on about the different areas of the college and warding spells is just dull. It seems my only option is to go to the very oldest of the eight saves I keep per character, which undoes all of the above, and I'm not even sure that'll work.
So, are there any fixes for this? Any patches planned? In the meanwhile, well...I have been wanting to go back to oblivion for a while, I suppose. "All energy flows according to the whims of the great magnet. What a fool I was to defy him."