Straight up to your questions:
The widget supports readonly attribute, but if you apply it before initialization then the whole widget will be readonly (expected behavior). If you would like to make only the input element readonly, then you will need to do this task manually in the kendoRendered
//find all numerictextbox inputs
//looks for input elements on the whole page.
The widget is designed to keep the up/down spinners enabled even though the min/max range is reached. This behavior cannot be prevented.
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