How to edit monsters and items:
Short answer: i dont know
Long answer: maybe you could do it with a little bit of hacking with an hexeditor or a trainer, or a combination of both... problem is, i don't have any idea about how you could get any result that could be used from within the queditor... i wish there could be a questmaker with good hacking skills out there to solve these problems...
Where to download machines:
have a look at my links page, "queditor" section
http://digilander.iol.it/malleusDS/links.html
that's all i know
Malleus