1) The last demon appears quite late, around day 100; it's Orlando. If he's already been killed, that's my mistake.
Upt: Dear asseco, if you're really in your 4th month, it means that for some strange reason, Orlando didn't appear, or (most likely) the quest simply wasn't completed. I'm not sure, but I think this might not affect the map's progress, as Sanctuary now opens in a different way. In the worst case, the failure to complete the quest may be (most likely) due to the fact that you or one of the players hired one of the demons as an assistant. Check if you've defeated all the enemies (the 2nd, 3rd, and 4th main quests to kill the Rebels, Demon Worshippers, and Demons, respectively), and/or remove the demon if you've hired him. Then, after completing all of the above + the "repel the demon attack" mission, Sanctuary will be opened.
Thank you.
That's exactly what happened.
I had Orlando in human form. On day 100, which is the 4th month, he appeared as a demon, but under my flag. It was both funny and frustrating. I removed him... and then nothing happened. I had to restart. Now I'm checking the tavern, but there's no hint yet.