Not sure if it is a general bug that can happen or it is specific to the beginning of chapter 5, but upon beginning the chapter, all that happened was the starting tile was displayed as dropping and nothing else. The only option that could be selected was to end the turn, which did not result in our heroes being placed or any more tiles being placed, but instead just raised threat and spawned enemies. Upon closing and trying to reload the app would just crash. Really unfortunate to see a bug of this scope, especially a little ways into the campaign.