I tried to reproduce the described behavior on MS SQL Azure with the database script you provided and the settings from the screenshots. The Telerik OpenAccess ORM versions I tested are 2012.2.816 and 2012.3.1012, and the Visual Studio versions are 2010 and 2012. However, everything works fine on our side.
I am sending you the assembly for OpenAccess 2012.2.816 with Visual Studio 2010. To run it just add your connection string in both App.config files and build the solution.
In the mean time I suggest you to create a new test application with a new domain model with the necessary setting and try your code again.
My best guess is that there is something wrong with the current model you use and in order to continue looking for the cause of this behavior, I will ask you to send to open a support ticket and attach the .rlinq file.
I am looking forward for your replay.
the Telerik team
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