Navigation was a little hard at the beginning, but I had got used to it (e.g., slanted arrow = nothing interesting, up/left/right arrow = you can go there, zoom in/out = checking something).
I had found a video tape about memories and played it. All I saw were numbers on the screen. Not sure what was going on. Then, I found an object in the mail box of the door. However, I didn't know what it was and how to use it.
I guess this is it.