Take note of the wall corners. It appears there is 5 corners in this room.
Here's roughly how I imagined the Men's Room:
| WASTE CONTAINERS
| EXIT DOOR
The particular drain and magnet doesn't appear like it would slide through like that. I dunno I was like no way will that fit, then poof it did?
I had kept thinking that maybe I was supposed to use the screwdriver on this instead of losing it to other thing?
My artistry skills are lacking
The scale of many objects changes throughout.
Once you use an object appropriately in the game, that object vanishes to keep things simple. There are no traps that will force you to start over. You can always advance from where ever you are in the game.