As to the installed version
, may I ask you to ensure you have removed all the previously installed versions as sometimes this may lead to problems. I tested installing the same locally and it works fine.
As to the Source Demos, it is mandatory to have the binaries installed and then all the referenced assemblies to be resolved fine. You may need to additionally Clean and Rebuild your solution. Furthermore, you can find attached an video illustrating how to successfully run the WPF Demos.
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