There is something, probably a visual effect, that causes me to feel nauseous and have a stomach ache, a bit like when you go on a plane or on a boat for the first time. I suspect it's the blur, a blurring effect that causes this for me.
Plus, it's really frustrating not to be able to run... why this choice? it is not logical to prevent the player from running, because this does not prevent cheating or having an advantage that would make progress easier, it is the opposite. You have to be able to run, because the character is too slow and it's annoying if you have to go to the upper floors to get the objects.
