Hi Jorn ,
You are absolutely right. The control templates for Office Black theme and Windows7 theme are different by design. The header discrepancy however affects the functionality of RadWindow in a way that seems wrong at this point. We will further test and consider changing this part of RadWindow design for Windows7. Thank you for your appreciated feedback.
Meanwhile, I attach here a demonstrative sample of how this behavior can be worked-around. You can search for NOTE in Telerik.Windows.Control.Navigation.xaml file to check the modified spots. I hope it will be helpful.
All the best,
the Telerik team
Explore the entire Telerik portfolio by downloading the Ultimate Collection trial package. Get it now >>