Honestly, all the vague "you're getting shot at" type applications of composure (as opposed to the drugs, negative qualities, etc that call for them specifically), I keep forgetting to make people roll composure. Oversight on my part, but it keeps the game moving forward. I intend to make a better effort of remembering to call for them when they finally meet some of the Infected in their natural habitat, or the more disturbing para-critters.
My players have actually gotten pretty good at rolling their composure checks for things like Flashbacks, Thrill Seeker, Compulsive, and Addiction without me asking for them. Their timing is great, too. If they're fudging the results behind my back, eh, sooner or later it'll come back to bite them.
As to Critter Power Fear & Composure, I'm with the rest of you, down with the Willpower Only check! Someone write it up on the errata forum.