How to add check box to list screen in SYCLO Agentry?

Hi,

How can I add a check box to the list screen. I want to add a new column which allows the user to select the check box.

I have tried with "Allow Multi-Row Select" option. When I selected this option I am getting an error

"The For Object defined for the "Transmit" action is invalid. 'None' is not a valid choice since the Multi-Row Selection option for the list screen is enabled."

-Shyam