Just to be clear -- Particular in a nested comp will not work with a camera from the parent comp the way other layers in the nested comp do, once collapse transformations is clicked. Yes?
So, I have Child Comp, which has Layers A, B, and C. Layer A has a Particular effect on it. Layer B and C are switched to 3D.
I put Child Comp into Parent Comp, and add Camera 1 to Parent Comp. I hit the "Collapse Transformations" switch on Child Comp. Camera 1 will treat Layers B and C as if they are 3D. However, it won't treat Layer A (Particular layer) the same way. In fact, it won't affect it all. Right?