I suspect this might be an error reported by the designer.Can you nevertheless try to run the example(F5 or ctrl+F5)? Errors reported by the designer are ignored by the compiler.
If that does not work can you try creating a fresh console application and add a model to it and create an entity with a Stream field?
I could successfully compile the sample on a clean machine with DataAccess version 2014.2.711.1 installed and hence have no clue at the moment why you cannot compile.
OpenAccess ORM is now Telerik Data Access
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