2, it may be related to the wardrobe. There is a hole behind the closet. Both sides of the closet can be opened. When you enter the closet, you think you can enter another room by opening the door. As a result, you fell down, and then the door behind the closet closed automatically.
When Xiao Qiang was looking for Kobayashi, he made a sound to make Kobayashi think someone was back, but Kobayashi didn't hear Xiao Qiang's signal, thinking that Xiao Qiang didn't keep watch, so he hid in the closet, and the mirror in the closet was replaced by glass to see what was inside. Xiao Lin opened the door behind the wardrobe and hid. As a result, he stepped on the air and fell downstairs. Maybe that's why Xiao Qiang couldn't find Kobayashi. Xiao Qiang was later killed by the wardrobe.