Hi Sameer,
Unfortunately, I don't see your screenshot.
However, I don't know of a way to do checkboxes, except with a boolean attribute. Remember that all attributes in Reltio are multivalued by default. Without seeing your screenshot, may i suggest that an RDM controlled list. The user could select a value, and then use the '+' in the UI to add another value.
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Gino Fortunato
Senior Solution Engineer
Reltio
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