Do you have SP1 of .NET Framework 3.5? The "no overload for method 'Begin' takes '0' arguments" error makes me think that the examples that crash have dependency to the SP and call methods that are missing in the non-SP version of the Framework. We will be releasing a service pack for RadControls next week and we will make sure that the example solutions can be built with .NET 3.5 with and without SP1.
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