Thank you for contacting us.
Generally, there should be no problem to apply any Telerik theme, as proposed in our documentation.
May you please share with us what kind of controls are you trying to style?
Our themes are designed to be used with UI for WPF and several MS Controls being supported by our theming mechanism. You could find the complete list of these components, here.
Any additional information about the assembly version you are currently using will be highly appreciated, as well.
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