An overview of the workflow for getting your Maya scenes into After Effects.
The best workflow to get planes into AE at the correct size/scale is to create them as 1x1 (unit) planes in Maya and then scale them up to the size you need (x, z).
Send to AE then maps the scale values of x > x and z > y in After Effects.
Note - this relies on Maya being in 'Y up' mode but this is the default and 'Z up' seems to break pretty much everything in Maya anyway.
(this post will get updated as we develop the plug-in)