The widget will not update all of its bindings when one is change from the scope. That being said, you will need to keep your scope synced if some of the fields are updated manually:
$scope.obj = new Date();
$scope.str = kendo.toString($scope.obj, "MM/dd/yyyy hh:mm tt");
Here is the updated demo
With regards to the second question, I am afraid that I cannot quite understand what is the erroneous behavior and what is causing it. Could you provide a Dojo demo that we can review?
Let me know if I am missing something.
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