Hello Will,
You can do automated builds with Surround SCM a few different ways.
First, Surround SCM does have integration with Continuous Integration tools, mainly CruiseControl and CruiseControl.Net. With these type of tools you configure an interval that it uses to check with Surround SCM if any changes have taken place in a specified branch and repository. If changes are detected, it launches a build.
Another approach is to integrate the Surround SCM Command Line Interface Client (CLI) with a build script. You can then use the OS scheduler to run this script at a specified time. The CLI command could be a simple recursive get.
Lastly, you could also use triggers in Surround SCM. When a specific file event takes place, you can configure it to launch a script. You have to be careful with triggers, however, because they are file based. For example, if you set the trigger to launch when you do a promote, it will launch the script once for each file that is promoted.
I encourage you to visit Seapine Labs (http://labs.seapine.com/). There are several helpful examples there, even an article titled "Automating a .NET Build With MSBuild and Surround SCM". Under the Surround SCM category you will find integration articles that can show you how to integrate with any of the CruiseControls and also trigger examples.
Hope this helps.