Change Height with MDL Vertex Modifier ?

I've deleted DeathKnight's horse by MDL Vertex Modifier,
and removed it's hero glow by NotePad.

I want to mount this model onto another creature,
but this Deathknight looks too higher to fit the creature's back,
so I also want to decrease DeathKnight's height.

At first, I thought that MDL Vertex Modifier can do it,
selected all and right-clicked to drag it down.
However, it became a mess of painting in game.

The question is:
"How can I change the model height in MDL editing?"

Maybe it's a noob question here, if so , I feel very sorry.
or can anyone tell me which tutorial should I follow to fix it?

hmm, is easier using 3dsmax, if u contact me at [email protected]; i will do it for u

Finally I made what I want with Geosetmerger,
(At first I tried to create special effect by trigger editor)
and found no problem wheh dragging geosets in MDL Vertex Modifier.

Thanks BlinkBoy, you are so kind.