On the campaign map 10 (The Kenos) are places where the rally flag is ignored by the minions (like when it is placed on an inaccessible tile) - particularly around the empire dungeon core in the center of the map.
One such place is the granite bridge before door leading to the empire's core. When the flag is placed on the tile just before the door, it is ignored by the minions:
Other tiles on the bridge work fine. It works fine after the bridge is claimed by the workers.
When the flag is placed directly on the door, it works - minions gather at the flag but they don't attack the door (I had to use possession to destroy the door):
One more (possibly related) problem - when empire's core health reaches zero, core is not destroyed but changes owner to 'Neutral':
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