Yes, you can achieve the desired functionality, using the templates of the MultiSelect. You can define both item-template and tag-template. The first will help you render the checkboxes and the second will help you in implementing the logic for the tagmode (single or multiple). Please check the sample example below, which demonstrated such implementation:
Also, note how the dataBound and change events of the widget are used, in order to achieve the correct behavior, when checking and unchecking items.
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