[DF2] Questions about map making

[dmux]

Hey everyone,

I've started playing around with the mission editor and have a few questions.

1. In one of the guides here on novahq, there's mention of using "absolute height" when doing z-positioning. I don't seem to have that option in the DF2med that comes with the Steam version of the game. I've also downloaded DFmedv43a (from here on novahq) and that version doesn't seem to have that option either. Does anyone know where I can get the latest version of the DF2 mission editor?
2. Is there a way to increase the hit points of objects (such as trees) to make them indestructible?

Thanks!