One of the new features of .NET Framework 4.0 is the introduction of Client Profiles. The Client Profile is a cut down version of the full .NET Framework that only includes the essential assemblies needed for client based applications. The idea is to reduce the download/install size for this common deployment scenario. Design time classes are not part of the client profile because they are implicitly only needed for designing and not for running your applications.
At the moment Krypton cannot be used in this situation because the Krypton design time classes are placed inside the same assembly as the relevant controls. So the Krypton Toolkit design time classes are inside the Toolkit assembly, Krypton Ribbon design time classes inside the Ribbon assembly and so forth. But the design time assembly is not included in the client profile and so the Krypton assemblies will not be loadable.
To enable this scenario I have now created a new ComponentFactory.Krypton.Design assembly and moved all the design time classes into it. This means you can write a client profile application that references the Krypton Toolkit/Ribbon/Navigator/Workspace/Docking assemblies and it will work just fine because the Krypton assemblies no longer reference the System.Design namespace.
Note that client profiles are a feature exposed in Visual Studio 2010 and so you will only be aware of them if you have downloaded and played with that version.