In case theath (me) isn't around, here's the steps that go into adding cc.rb:

1. ssh into the cc.rb box (ci.ngenplatform.com)
2. su theath
3. cd ~/cruise
4. ./cruise add <ProjectName> --url <svn url>
5. killall -9 ruby
6. ./start

Your build will probably fail at first. To trouble shoot it, you can find it in ~/.cruise/projects/<ProjectName>

In that directory, you'll see a work directory (where the svn checkout resides, and the code that cc.rb uses to build), several build directories (handy if you need to check some different logs from the  build), and a cruise_config.rb.

If you want cruise to do some magic stuff before your project is built (or build it a special way) and you're using Ruby, you can define a Rake task named 'cruise' that will get executed automagically. If you're not using Ruby or you need something besides 'cruise' to happen, you can edit cruise_config's project.rake_task or project.build_command (one of those needs to be commented out; they'll step on each other's toes). 

For a Java project, for example, you'd set the project.build_command to something like "ant build test."

You can also set email notifications in the cruise_config, so if you want to receive a friendly reminder that your build is failing any time someone checks in something that fails, go ahead and do that.