After I've pick up Pallegina I go speak to the Ambassador.
(I did not go there directly after getting Pallegina)
Conversation starts, I pick the first option (Diplomatic, "Hear her out")
The conversation window is stuck open and I need to exit with ALT-F4.
Steam Screenshot: http://steamcommunity.com/sharedfiles/filedetails/?id=415881433
I have a save game, directly before the event, but it's too big to upload.