Subassemby Composer Tutorials
You can employ the playlist icon in the video control to play any of the 10 available videos in this series.
A series of basic to advanced video training tutorials on the Civil 3D Subassembly Composer in a playlist.
Shawn Herring of ProSoft delivers a great set of tutorial videos on the SAC for Civil 3D.
From the ProSoft YouTube Channel
I always have to remind people that you should try employ the existing Civil 3D Point, Link, and Shape namespace in your PKT files as much as possible.
This simple discipline reduces the annoying requirement to add the unknown Point, Link, and Shape codes into any existing Code Set Styles.
Look for the C3DStockSubassemblyScripts.codes file in ..\ProgramData\Autodesk\civil 3D version\enu folder of your Civil 3D install.
Editing the PKT files supplied with Civil 3D or that you get from others is worth the small amount of hassle to reduce the downstream production wasted time.