This is a really cool tutorial, but I need help to do the same thing using polygons instead of dots. How should I modify the code to do this. P.S. Excuse me for my really bad english.

You need to be able to load faces as well instead of only points for it to work.
Unfortunatly you allso need to create a new dataset for it to work, and last but not least, morphing with polygons is not as simple as morphing with vertics, it's pretty easy to run into a situation where polygons are pointing everywhere in a horrible jumbled mess.