Hi Richard,

To make it easy for you I just created an external Hello World Module and added it to svn /trunk
If you get the latest code from svn trunk you can see how it works. You will see the new Class library project named SampleExternalModule.
The module consists of the module control and an edit page. The code behind file for both the control and the edit page are in the SampleExternalModule class library project.

These are the steps I took:
1. Create a new Class library project in the solution to contain the code for your external module.
2. Add a Reference to System.Web and also to mojoPortal.Web (I used a project reference)
3. I put the SampleExternalModule.ascx file in the Modules folder of the Web (though you could put it anywhere in the web)
4. I put the SampleModuleEdit.aspx file in the root of the web

both the ascx file and the .aspx file inherit from classes in the class library project
the .ascx file class file (in the class library project) inherits from mojoPortal.Web.SiteModuleControl

When I build the solution I want the dll from my class library project to be copied to the bin folder beneath the web so I right clicked the class library and went to properties > Build Events and added a Post Build Event Command Line like this:
xcopy $(TargetPath) $(SolutionDir)\Web\bin

Now whenever I build, the dll goes in the bin of the web and the module works as expected. To make the module available for your site go to SiteSettings > Feature Modules and click Add Module. Enter the Relative path to the .ascx and give the module a name and now you can add it to a page.

Now when packaging up the app it is optional whether to include the external module. To include it just put the dll in the bin and the .ascx and .aspx files in appropriate places.

Hope it helps,

Joe