This has potential. I liked how clear her facial expressions are, it makes it easier to understand what's going on. I didn't mind the lack of detail too much, it has a unique appeal. Fix the color scheme a little, try adding a wider range of colors. Some of the colors make it hard to distinguish certain objects. Also, work a bit more with the movement of the characters to make it look fluid, some of it looked kinda choppy, or went by too fast.

Other than that, I liked it. The music was well suited to the story. Some environmental ambiance would work wonders with this, too. (the sound of the train)

Thumbs up from me!