This error is a result of a bug in Visual Studio: http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=379324. I am afraid we cannot overcome it on our side.
Currently, you can use the following solutions:
2. Simplify the Visual Studio solution's hierarchy by referencing an output assembly instead of referencing a project.
For instance, if the error mentioned the <YourSolutionName>.Module assembly, then you can reference its output assembly (<YourSolutionName>.Module.dll) instead of having its source added into your Visual Studio solution.
3. Use a standalone Model Editor tool (%ProgramFiles%\DevExpress 15.2\Components\Tools\eXpressAppFramework\Model Editor"
Regarding the bug, Microsoft said that they couldn't fix this problem of Visual Studio. So, I have posted ( http://social.msdn.microsoft.com/Forums/en-US/csharpide/thread/b7ee8b92-335d-4118-b609-eb7825c7d1a4 ) on their forum to see a feedback from other users and to gather votes or find a workaround for this issue.