I just tried this control and within 3 minutes, I customized it to get the perfect image editor for my project. My only issue is about localization (in french).
I can directly edit header and tools labels within XAML but some tools open a custom side-pane with non translated controls. (i.e. Draw tools => brush size, brush color). I don't know why this component is not localized. I tried several things like "Language="fr-FR" in XAML or even C#
From what I understand, localized strings are in Telerik.Windows.Controls.dll so they should be charged. Even more weird, when I run the WPF Demos, I can success to run the Localized version of this control (the demo where you can choose between english, german, french)
Thanks for any help
ps: I have the very last version of UI for WPF (2016 R3)
info: I'm running it in a VSTO for Office. Not sure that changes anything but I prefer to give all information