Thanks for looking gents.
The thing is, what I want to do is distort the cylinder created by the mask. It seems the mask masks the entire tree, rather than just the node it's attached to, which to be honest, is quite useless. Can we not localize effects rather than it dominating the streem? Can we not say "effect this only"? The more I've played with the cloud system in TG, the more I hate it. The way it's set up, we can't get any large scale variation in the coverage shapes, which having access to modulating the cloud node's altitude and depth would seriously help. But on top of that, being able to distort a basic shape would be kind of useful too, and PF's seem to be very limited in that aspect.