In the abandoned house, a young female zombie with a red dress can be seen lying on the floor with a bullet wound in her head. When the main characters are fleeing the house, she can be seen with the other zombies trying to get in the jeep.
During the Mask Ceremony scene. The masked celebrant takes off his mask and hands it to Lia. This is not possible in a mask ceremony. In a mask ceremony, a man who takes off his his mask is no longer considered the man he was before he put on the mask. It is not possible that a man would take off his mask in the middle of a mask ceremony, let alone hand it to an obvious stranger.
After Pierre is killed in the elevator. Zantoro shoots at a zombie missing an eye. He clearly fires his machine gun into the zombie's chest. A close up shows the male zombie squirm and fall backward dead from the shots. Which is incoherent because Zantoro (and other characters) know the zombies can only be killed by head shots or incapacitation to the brain.