The documented process is, if the box was checked, it would show the checked value (Y), and after opening the edit window, the box would be checked. If the box is unchecked, it would display the unchecked value (N).
Upon further exploration, it was demonstrated that if the check box is selected, the "Type" is properly changed to a "Boolean" type. However, you can change it to "String" if you want. This was done by accident to attempt to make logical sense between (Yes, No) rather than (True,False). In Datamaker, it works as a Boolean even is the "Type" was selected to be "String". In TDM Portal however, it is treated as a "Text" box and not a "Boolean" box.
As a workaround, the "Type" was set to "Boolean" even if the two values to choose from were (Yes/No), (Black,White), or (US/UK).