Try using the AddObjectCreatures(...) function.
You can display a message by simply setting the dwelling to a non-working state, then using a QuestionBox. If the player agrees, a battle begins; after the battle, the dwelling returns to its working state.
Сценарий "Изгой"
Сценарий "Этот мир сгорит дотла!"
Кампания "Воин Ироллана" в процессе... 45%
[/spoiler]