The problem with the Poser update (I have Infinite) is that any change you make to the material zones causes Vue to lose all your material changes when the figure is imported the second time.

So let's say you want your Poser figure to have shinier skin. Edit the material "SkinTorso" and get the effect you want. That's fine. But now you need the same edits to SkinHip, Skin Neck and the rest. Logically, you should copy the edited material to the other parts of the figure. But this causes Vue to destroy all the material zones you copy to. Now when you change the figure in Poser, Vue tries to import it again, can't match the material zones in the pz3 file to what it has locally, and defaults to all the old material settings. Really stupid, that.

If there's one thing e-on should fix in Vue5 before they do anything else, it's this absurd compulsory merging of material zones. It causes so many problems, and would be really easy to fix.

As to posing feet on terrain, the easiest solution is to get it roughly right in Vue and then fix it in postwork. Remember Phantast's Golden Rule: "Never spend an hour trying to fix something in a render that can be fixed in a minute in postwork." Apart for the foot actually intersecting the ground, the key visual clue is shadows. A little bit of editing with the clone brush and your figure's foot now looks like it is firmly on the ground even though it isn't.