Spark does not need MSMVC specifically for master layouts and views to work together.
But unless you specifically provide your own version of IDescriptorFilter , IDescriptorFilter will be used, and it expects the Application.spark file to be in a folder named Shared or Layouts under the main Views . If it is located in one of these two, you do not even need to refer to it from any of your *.spark files, it will be used traditionally because of its name and location.
What about everything that I can say from the information you provided, but I think it could be something else, and I will need to see some code or example to help more ...
Hope this helps, Rob
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