While working on this sample, I came across the following errors:

1. I needed to change the version of .NET from 3.5 to 4.0 in the properties of the project.
2. I got the following error when I compiled the error: The type ‘Microsoft.VisualStudio.Modeling.ModelElement’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘Microsoft.VisualStudio.Modeling.Sdk.10.0, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a’.    C:\Projects\Microsoft.Practices.ESB\Source\Samples\Designer Extensibility Samples\Extenders.Itinerary.OrchestrationSample\Extenders.Itinerary.OrchestrationSample\OrchestrationSampleExtender.cs
3. This made me install the following components:
4. This then required me to reference the following assembly in the project: C:\Windows\Microsoft.NET\assembly\GAC_MSIL\Microsoft.VisualStudio.Modeling.Sdk.10.0\v4.0_10.0.0.0__b03f5f7f11d50a3a\Microsoft.VisualStudio.Modeling.Sdk.10.0.dll
5. Once I built the two projects, in the directions (step 7) it states: In Windows Explorer, open the \Lib folder under the Itinerary Designer install path. This actual path is: C:\Program Files (x86)\Microsoft BizTalk ESB Toolkit 2.1\Tools\Itinerary Designer\Lib\