I was able to reproduce the behaviour by following the exact steps. I can confirm that there is a problem, however at present we are not sure what causes it. The fact that validation does not work the first time, but works after submit button is pressed suggests that the problem might be related to jQuery validate (Kendo Numeric text box does not change after the submit button is pressed).
We will log this case for further investigation. I am afraid that at present I cannot say when or if this will be fixed, as we do not know the root of the problem yet.
Please accept my apology for the inconvenience caused.
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