There are five basic steps to editing S3D in Vegas Pro: synchronization, preview, alignment, grouped editing, and final output.
This tutorial will explain each step in detail

There are five basic steps to editing S3D in Vegas Pro: synchronization, preview, alignment, grouped editing, and final output.
This tutorial will explain each step in detail
The key to understanding overlays, masks, transparency, and compositing is to understand the parent/child relationship between tracks.