Staterkit for DNN 5 has some trouble with FCKEditor assembly. I am trying to figure it out and found a solution in Visual Studio 2008. You just need to add reference in Visual Studio, just browser to /Bin/Providers/DotNetNuke.FckHtmlEditorProvider.dll and add it as reference. It should move the FCKEditor assembly to /Bin/.
DotNetNuke 5 is new heaven for developer who loves JQuery so much, you don't need to injecting the core of JQuery to DNN. DNN Developers trying to be TableLess friendly layout, give it a try and Happy New Year 2009.