Revealing mistake: In the close-ups of the elves during the Coronation Ball, you can see the fishing wire used to attach their wings to their backs.
Revealing mistake: In the close-ups of the Queen as she dies, you can see the line of her wig on her forehead.
Audio problem: When the Queen is speaking to the Troll King for a second time in the mirror, she wraps up discussion with him and in the next shot she walks over to her mirror and says, "Mirror, talk to me, why haven't you found Windell yet?" The Queen's mouth moves ahead of the actual voice.
Snow White: Why did I let her in? Didn't I know she was bad? I did. Of course I did. But I also knew that I couldn't keep the door closed all my life just because it was dangerous. Just because there was a chance that I might get hurt.
Answer: It's the sound of his bad luck coming.