I'm currently working on some small projects and an enterprise level case study project where I decided to use SubSonic which is a lightweight open source ORM for .NET led by Rob Conery. I can say that SubSonic is really lightweight and is really easy to use, but as might be expected has some minor configuration overhead. SubStage developed by Eric Kemp is a must have if you are using SubSonic, but this tool lacks a very important feature IMHO. All your subsonic related project configuration is kept inside a predefined MasterStore.xml file which means you only have a single file for all your subsonic projects. In this scenario, it is not easy/handy to attach your substage configuration to your project source code.
To overcome this problem, I modified SubStage source code (built against SubSonic 2.2) and added "Load Master Store" and "Save Master Store As" File menu items. I posted the patch to Eric Kemp but I do not know if the patch will be applied in newer versions so I publish both compiled SubStage and the Subversion Patch file.