If you try to load a predefined theme in your project and run the project without a debugger, you may get a missing resource exception. The solution to this issue is:
Assembly lAssembly = Assembly.GetAssembly(typeof(Telerik.WinControls.Themes.Office2010Theme));   
Telerik.WinControls.ThemeResolutionService.LoadPackageResource(lAssembly, "Telerik.WinControls.Themes.Office2010.tssp");