Some basic questions and issues after some days of utilisation.

re: Anchor Point vs Position (Parenting) & Point Controls in Effects

These two are related issues, relying on an understanding of "Composition Space" vs "Layer Space."

This stuff can be a little tricky to wrap your head around at first (and takes a while to write out explanations). Fortunately, I've explained these concepts in videos already, so I'll just refer you there to start:

This video will both explain this concept of Comp Space vs Layer Space, and also offer some solutions to common questions:

https://www.youtube.com/live/xeBrtrrKDVA

A short summary:

Position is actually the position of the layer's Anchor Point in Composition Space.

...until you parent that layer to something. The child layer's Position is now the position of its Anchor Point in the Parent layer's Layer Space. (That's why the Position value changes when you parent a layer.) The Point controls within effects add another layer of complication here (a different but similar issue, which can also be combined with the above idea to make it even more confusing - ha!)

Hopefully the above video will point you in the right direction - once you've got your head wrapped around that, let us know if you have more questions!

re: Track Mattes / Set Matte

Yes, the Set Matte effect works differently from Track Mattes, though they have some overlapping functionality. 

Here's a good overview of Track Mattes, respecting the recent updates to this feature: https://youtu.be/rvAXZl8Ypus 

Here's a good overview of Set Matte: https://www.youtube.com/watch?v=zfmuXUgATpo

Personally, I mostly end up using Set Matte for textures (like in Jake's example), or to matte a layer with itself. (Example, you get a logo from a client with a white background instead of transparent; you could possibly use Set Matte, set to luminance, to use the layer's own white/black values to cut itself out.) It does have a "gotcha," in that it requires your layer and matte source to have the same dimensions (which usually means pre-composing). In short, this new Track Matte functionality makes a lot of what Set Matte *used* to be needed for obsolete, so if you can't understand how to make it work quite yet, direct your energy at Track Mattes. 

None of what you experience is out of the ordinary. It's just how AE works. Effects always reference layer coordinates while at the same time this principle falls apart with shape layers because they are just comp-sized containers for the vector rasterization engine. Same for your track matte issues. And, to put it directly, from your description you are making the typical mistake of considering pre-composing the enemy and trying to do as much as possible in the same comp/ on the same layer which simply cannot work given how the render pipeline works. Instead you need to consider it a regular part of the workflow and plan your project accordingly. Aside from the abstract explanations laid out in the online help and what we can tell you here on this forum this is simply a matter of of experience. The more projects you do, the more you'll understand these minutia and eventually it will simply "click" and no longer be a problem.

Mylenium