Most changeling/chrysalis music I've heard have been This Day Aria remixes, but that doesn't really fit what think of when I envision an invasion of shapeshifting insect/zombie monsters.
So here's my take on some changeling inspired music.

I used True Strike for some of the percussion, LA Scoring Strings for the orchestral strings, and the Factory Kontakt 5 library for the horns. The rest of the percussion, the sound effects, the plucked instrument and the violin was recorded by me. Some of the sound effects were made by bowing a guitar with the violin bow (how cool is that!?).

Video made in After Effects

320kbps .mp3 download (Right click, Save as):