ADO.NET Entity Data Model extension not working

I want to develop a Visual Studio extension to add extra properties on entity types. As suggested in the answer to a related question I had asked before, I have installed the ADO.NET Entity Data Model Designer Extension Starter Kit as the first step.

However I can't get it working even if I simply build and install the starter kit project as-is: the extension gets installed and I can see it in the VS extensions manager, but I can't see the extra properties in the entity models I add to my projects.

Things I have tried so far:

• Enabling support for VS Ultimate in the extensions.vsixmanifest properties page (as this is the VS edition I am using).
• In the "Content" pane in the extensions.vsixmanifest properties page, removing the existing entry (of type "MEF content" and path pointing to the generated DLL) and adding another one of the same type, but referencing the project itself instead of the generated DLL.开发者_如何学编程
• Running a standalone VS to test the extension / forcing a new instance of VS to be open by running the extension project itself (the extension being previously installed in both cases).
• Adding extra flags to the constructor of the EntityDesignerExtendedProperty attribute of the MyNewPropertyFactory class (to include the storage model besides of the conceptual model).
• Generating a test model from scratch / from an existing database.

Nothing of this works, it is as if the extension was not installed at all. What else can I try out?

(As a side note, if I try to debug the extension the breakpoints I have placed appear as disabled, with a tooltip stating that "no symbols have been loaded", I don't know if this may be related to my problem).

My working environment:

• Windows 7 Ultimate 64 bits
• Visual Studio 2010 Ultimate SP1
• Visual Studio 2010 SDK SP1
• Entity Framework 4.1

Thank you!

Turns out that it was my fault... I violated the number one rule for diagnosing problems: change only one thing at a time. Arrrrgh... :-(

So the correct configuration starting from the initial state of the starter kit project seems to be: add VS Ultimate support but do not change the "Content" pane (leave the reference to the DLL as the content path).