Ok, so in the starting room there's 4 doors. I'd approach doors on the left/bottom/right/top etc. Sometimes it would just act like there wasn't a door and I'd just "hit the wall". At other times, I'd pass through the door into another room - but then instantly on the room appearing there would be a noise and my character would be returned to the starting room. I repeated that a few times until the game told me I'd died and then gave me a nice message :D I tried on different resolutions/screen sizes but it didn't seem to make a difference as to how I could either go through a door or "hit against it". I couldn't seem to find a repeatable method for getting through a door.
Ok I think I know what your issue is... You're not pressing E to go through the door. That's how i intended you to go through them as it was easier to program. The dying when going through a door is just you falling as there's no ground under the walls (and in hindsight that was very stupid). The reason you sometimes go through walls and don't other times is because that is one of the intentional bugs that gets randomly selected.