Very nice game, it's very pretty and plays nicely!
The controls are mapped to latin keycodes instead of physical keys so non-QWERTY keyboards might have some issues playing, I was surprised that changing the keyboard language fixed it for me because I had a lot of cases where it was unplayable with an AZERTY keyboard, even after changing the language.
It took me a while to realize that I could "scroll" the messages by dragging the mouse, instead of a very slow scroll with the mouse-wheel, so it was annoying having it also bound to the scale mechanic. Maybe try to unbound the mouse-wheel for the messages if it's possible.