I had a thread up earlier in which someone told me that I can edit height by editing the "scale" of the topN bone (after renaming it TopNull).
I tried this, as you can see here:

When previewed, you can see that his proportions have been altered.

However, in-game he is back at his default proportions:

This was supposed to have been a one slot mod. I brought up an alt costumed Cap Falcon in-game and they are the same height. Pico should have been significantly shorter now.
Did I miss a step or do something wrong?