The internal build is available in your account as well. Feel free to give it a try and let us know whether your issue has been fixed meanwhile.
When adding a new Telerik Report item make sure that its name includes the latest installed version (e.g. Telerik Report Q2 2014
(Blank)). In this case the Upgrade Wizard should not run.
For the sample project we don't need the entire code base. Two reports with the respective data sources which reproduce the issue should be enough.
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