I don’t know what I’m looking at in your screenshot because I don’t use that tileset. However, I do know that winches are finicky. There’s a post . . . Bah, couldn’t find it.
The ones I’ve used (t_gates_mech_control) requires that you place it next to a t_wall or it doesn’t work. And that t_wall has to be attached to the locked metal door. My guess is that they’re all pretty sensitive and I wouldn’t mess with them unless you’re patient and good at puzzling things out. Best I can say is to look at the default layout and work backwards, but you probably know that.
EDIT:
And yes, if a coordinate is represented by multiple numbers the object will spawn in one of those locations. So, an item at coordinate x: [ 21, 23 ], y: [ 7, 7 ] has a chance to spawn at 21,7 22,7 or 23, 7.
Also, y: [ 7, 7 ] is the same as y: 7. It’s written both ways throughout the game files and although the brackets make it look nicer I don’t think that’s a hard rule.