You're right, that sounds really weird! These are both technical and artistic choices. I'll explain it to you.
Basically I wanted to make a short game with a simple scenario because it is my very first game. Since there is no inventory or map to find your way around I did not want to make the whole house accessible . However, the player sees in advance the outside of the house.
I wanted to respect a certain architectural logic by putting a few doors that reminded the player that the house is indeed bigger than what he has access to.
Making them inaccessible reinforces the fact that something or someone seems to be pulling you down a specific path.
But in terms of pure gameplay it is true that these 2 doors can be confusing.
As for the empty sword display, this is one of the few foreshadowings that I put in the game. If you don't know that word, this is a process of inserting more or less subtle elements in the heart of a story in order to give the protagonist a clue about his final destiny.
In this case, if the sword is missing, someone is currently using it to slice something.
in the same style, you have the patterns of the 1st enigma which represents a sword, a head without body and a plate.
There are also the three chairs in the reception lounge. 2 are on the ground and only 1 is still standing. it is a metaphor for the guests.
I'm not going to quote them all, but I think it may have helped you understand some of my choices.