Insert or Add new row

Hi,

We have a requirement of dynamically add or delete dropdownlist on click button.

I could see there are custom action for Add Row and Insert Row, but it always ran into error saying either "From" or "To" is missing.

Looks like these actions are only available for table and not for forms?

Please let me know if anyone has tried/achieved something similar.

Thanks in anticipation

Prashil Wasnik