Factual error: The gazette clipping at the beginning of the movie where Velma wrote her disdain for Carol is dated Thursday, March 25. Neither year when the story could be taking place based on other hints had March 25 happen on a Thursday. (00:03:50)
Factual error: Daphne gets a bit of water spilled on her from a glass at lunch, and she stays with the wet patch (which is just water, as stated) throughout the whole day, arriving at home when it's dark with the same wet spot visible. With all the toweling she did, and even simply by body temperature, the little dampness should have been dry by the end of the afternoon. (00:21:50 - 00:31:40)