Though maybe not a bug, I notice when in ambush is you kill the priest from the opposing tea, this is happening:

Kurilia is no longer affected by the Aura of Physical Protection
Kurilia is no longer affected by the Aura of Magical Protection
Kurilia is no longer affected by the Aura of Bravery
Kurilia is no longer affected by the Vital Aura

Lady LaLa sent out an Aura of Physical Protection (SL 40) over Lady LaLa's Party : Phy. Dam. Reduction +40

Lady LaLa sent out an Aura of Magical Protection (SL 35) over Lady LaLa's Party : Mag. Dam. Reduction +35

Lady LaLa sent out an Aura of Bravery (SL 35) over Lady LaLa's Party : ATT +105

Kurilia is one party, LaLa in the other. It does say in Turn 0, they are both releasing their auras, so I think it is not so much a bug, just some writing misplaced in the code?

Also, pretty sure Curse isn't working at all for priests, but is definitely not working for the monsters in Not Dead Yet. Maybe Curse was messing up the quest before, so you fixed the quest by removing it? I do not know, but thought should tell you.