Christmas Eve, when Dorothy Wynant meets Nick in a bar, she says her father disappeared 3 months earlier. But the opening of the movie, which depicts the day in New York that her father disappeared, it is snowing. Late September is too early for New York City snowfall.
Wynant removes his eyeglasses when he realizes the bonds are missing from the lock-box and he turns to Tanner. As he steps towards Tanner however he is wearing his glasses and removes them as he speaks.
Early in the film, after Nora gets dragged by Asta to find Nick, we see Nick explaining to the bar manager that Asta is a well trained dog. Initially, Nick has Asta's leash in his right hand and points at Asta with his left, but when they focus on Asta, Nick is pointing with his right hand and obviously holding Asta's leash in his left.
When Nick and the coroner look at the body through the Fluoroscope, the bullet, and a piece of shrapnel, appear as bright white. The Fluoroscope uses x-rays except it is viewed on a screen instead of film. Dense objects, such as bones, appear dark, as it appears in the movie. The bullet and shrapnel should then be even darker as it blocks even more of the x-rays. However, this would not have shown up well in the movies, so they were made bright white so the viewers could see them easily.