Thank you for the nice words and for your interest in Kendo UI.
With regards to your questions:
1. All Kendo UI widgets have configuration options which allows the developer to change the UI messages. The developer can localize the widgets through them. You can find detailed information and code samples in following help article:
2. This feature is not supported out of the box. For such scenarios the developer should write custom code which will determines the visible/initialized components based on the user role.
3. Kendo UI Supports various accessibility standards. For more information on the subject please check the following help topic:
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