The GUI does not seem to be properly scaled when playing on the normal resolution given on the website. This made the "Money +25" and such text be shown offscreen.
This also caused the inventory slots to be offset from where they really are. So for example, if I equip a weapon, I have to aim a little bit to the right from where it really is to equip it on the right slot.
Also clicking on the X button on the inventory does not work.