Along with the new look, AUTOCAD CIVIL 3D 2014 adds some important .NET API to Corridors and it's constituents like Assembly, Subassembly, BaseLines.
Now, we can add / create Corridor using Autodesk.Civil.DatabaseServices.CorridorCollection.Add(string corridorName) and its overloaded methods.
We can access/add/remove Baselines using the BaselineCollection class as well as modify Baseline properties.
We can add and remove a Subassembly as well as Import a Stock Subassembly (ImportStockSubassembly()) or Subassembly (ImportSubassembly()) from an ATC file.
We can Add Assembly and ImportAssembly as well.
Apart from Corridor, other API enhancements include features like Section View Groups, SectionView, Sections etc.
For all the details on what's new in AUTOCAD CIVIL 3D 2014 .NET API, I would suggest you to take a look into Civil 3D 2014 wikihelp's "New Features in the .NET API" section.
If you are using COM API, please note the following update -
If you are using the COM API, you need to update the object version to 10.3 (from 10.0 used in AutoCAD Civil 3D 2013). The objects and interfaces exposed have remained the same, but you should reference the new libraries, which are installed by default to: "C:\Program Files\Common Files\Autodesk Shared\Civil Engineering 103".
Stay tuned for more articles covering new API features in the coming days!