Implementing an External Activity
An External Activity is a .NET assembly made available as a Template Building Block in Content Manager that implements the business logic of your Automatic Activity and/or Activity expiration script.
External Activities and C# script Activities
Implementing an Automatic Activity or Activity expiration script in C#
Creating and uploading the .NET assembly for your External Activity
Implementing an Automatic Activity script or Activity expiration script
External Activity sample implementation
Creating an Automatic Activity in Visio Workflow Designer