You can get all the styles from the Summer theme. Add x:Keys on all implicit styles so they don't turn your app Summer and reuse the templates from the resource dictionary. Note this is especially easy using Blend. When you merge the so modified xaml resources in App.xaml you can create an implicit style that applies to all RadPane's and sets their DocumentHostTemplate to the same template used in Summer. I am attaching an example project with the modifications done.
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