I'll try to keep this as short as possible.
My legendary engraver didn't like my new floor plans, which included the removal of some of his works (oops) and tantrumed. Guards didn't like it of course and issued some beatings and jail time.
At this point (probably) something went wrong. The engraver conducted meeting with mayor and got his sentence reduced. I don't whether it was during this meeting or after that, the guards dragged him to jail. Anyways, while in jail, the engraver was still "Attend meeting" and mayor tried to "Conduct meeting".
Time passed and the human caravan came with trade baroness. As the mayor was trying to "conduct meeting" with the engraver, the baroness had to wait. More time passed and the engraver finished serving his time in jail. Instead of conducting the meeting with the mayor the engraver went "No Job" and stayed in the jail. The engraver goes to sleep in his own quarters, goes to eat and drink from the stockpile, but after that returns to jail and idles there.
Now the dwarven caravan came and went and the liason is also waiting (with the baroness) for the meeting with mayor. Mayor's state is "Conduct meeting" all the time (when he's not sleeping or eating or doing some other thing), but no meetings take place (probably because mayor still tries to have meeting with the engraver).
I have a save of the situation, but won't spam Toadyone with it unless he wants to have it.