Indeed, the ReportViewer xaml file is not included in the theme assemblies provided with UI for WPF suite and I understand this causes inconvenience when using the NoXaml dlls.
I will forward your request to the development team to consider a more suitable way for referring the Telerik.ReportViewer.Wpf.xaml resource in such a scenario.
We will update the thread as soon as we have more information on this.
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