Have you changed something on Lily's quest? I haven't been able to get it to work these last few days, and I'm not sure if it's because I've been rushing it a bit; I asked if she had a quest but not the specifics of the flowers, and when I brought the flowers I clicked the 'tell me about the flowers' dialogue option and got a blank dialogue box (with the fox icon). Then I couldn't move till I opened the stats screen or the skills screen, and the blank dialogue box stayed up till I went in the mine.
Seems like it might be connected with King - the times I couldn't do Lily's quest, I'd gotten the emberheart from the standing stones to summon King and did King's quest before getting the flowers for Lily. This time I got Lily's emberheart, used that to summon King, did King's quest, and when I reached Pierre and tried to talk to him I got the blank box. I could still talk to King, but only King. I collected the standing stones emberheart, but I couldn't use it on a campfire - I tried the one in the mines first, then the one at the sawmill. Neither worked.
found it. it was king related as he is the only one that has a text entry dialogue option. entering text and talking to someone else cause them to try and fill in data to a non existent variable so dialogue system crashes. fixed now and i also fixed a few other problems with the dialogue system and removed unused code so hopefully something like this wont happen again.