I'm having a hard time with the moving crate. I've finished my design, and am ready to commit... but I can't get stuff to go in the moving crate! I'm tried placing walls over it, but it's not taking. I'm going to have to remove everything manually (and that's going to be a pain!) Some things went in, but not everything... I can't figure out what I'm doing wrong. I try all kinds of things, but nothing worked! Any special trick to moving regular locked down items and such into the moving crate that I'm not aware of?