Camera movement is affecting stroke Trim path (connected to Nulls in 3D)

[HaroldDurnez]

So, I've created a long stroke with many path points which draw the stroke up and down. (Like a heartbeat EQ)
I then(using the Create Nulls from Paths tool in Ae) applied the 'Points follow Nulls'
This turns every path point into a Null controller.
Switching all of this to 3D allows you to space out the Nulls and create a 3d like stroke.
I spaced out each milestone around 500pixels in Z apart.

Now, you simply add a trim path and as expected it can trim this 3d path from 0-100. Great!

However, my problem is that as soon as you create a 3d camera, and you move to target each of these milestone points, the Trim Path gets affected too, thus throwing it out completely!

Anyone have a solve for this?

I imagine it might be the likes of connecting the Nulls to the camera somehow.

[Rick Gerard]

Paths only exist on the XY plane. You have to add an additional null for each of the original nulls created by the script, make them 3D, then add an expression to the original nulls that use a toComp([0,0,0] expression to convert the 3D nulls position to comp space to layer space for the 2D Shape layer with the path. You can now move the path in what looks like 3D space. The Bézier handles will get fouled up unless you use Create Nulls From Paths Extended (search for it) also to add nulls for the handles; the path would really be 3D, and there will be no perspective, but you'll be able to move the path to fairly closely emulate an actual 3D path. 

Show us a screenshot or give us a detailed design description, and we may be able to help you figure out a viable solution.