'Tilean Days' is the only example I've come across -- & it seemed a fairly unusual use of Mordheim to me. Though it should be easy enough to come up with an alternative, if the GM's running the 'hostiles'. Like 'Kidnapped' where the GM controls the cultists (or whatever) & the players have to rescue the fair maiden. Or a monster hunt or assassination mission, where the three players have to work together to kill a specific target, like a cult leader or a powerful vampire.
Just some ideas, in lieu of more helpful help.