A: Looks like a minor issue. Turns out CS5 has a bug converting the particle engine component into a "Sprite". There's a superfast quickfix.

1) Open particleemitter.as in the com/patrickjansendesign/particleemitter/ folder, change public class particleemitter extends Sprite to public class particleemitter extends MovieClip

and

2) delete the first frame in Library Component "particle emitter" so you get a single frame with the particle instance left on stage
(tip : select that instance on stage and set alpha transparency to 0% to make sure there's no initial single frame flicker)