The Ladder [SPOILERS]

[Guest7]

I'm at cave/cellar of sorts, where the wire-cage room is. I drug that ladder and hinged it on the trap door. Then I went back to look around and there was a big crash. When I returned to the trapdoor, the ladder was gone. I went back into the caves and found it again. Does this ladder go to THIS trap door, or do I stack the crates to get back up. I don't want to put the ladder on again and then have it disappear back in the caves again.
Thanks for the help. I just started this game today. So, far no monsters, only spiders and that dog. And the tech-ability to float some of the objects in air, is just awsome!