I'm gonna go out on a limb here and say that the best part of Castle Sweet Castle was the new song...

Image was taken directly from a google image search, but I believe that google got it from youtube channel MylittleBronieDE.
https://www.youtube.com/user/MylittleBronieDE

Mp3 Link: http://www.mediafire.com/download/dj5rfcttdr3aagj/Make+This+Castle+A+Home.mp3