Awesome, you rock! So that's about what I was expecting, and now I'm looking for:
1) Someone with AE experience to tell me whether AE just is bad for compositing or if there is a fix
and
2) Enough...

Sure thanks Dave, sent. For a nuke workflow, should the the passes and/or render layers by premultiplied?

Well, I'm here again. Still am not able to use ID passes effectively. Even the MILA matte pass built into the new mental ray render settings.

I've got a very basic comp with 2 copies of an image....

As I understand it, creating a material or object ID pass is pretty common practice, using surface shaders with a single color (typically Red, Green, or Blue, and additional ones might be Cyan,...