Selecting another Field, for a Column, in a User List?

When I create a user list I can select from a drop down list which field should be listed in which column.
However, not all fields are available in the drop down list, (such as FirstName, nor Email).
How can I include those fields in the drop down list?
(Why are they not there initially?)

The fields need to be published and set to display on profile to be available for display on a list since it respects profile display access.

Thank you.
The confusion was about the relations between the various "name" fields, and how they are defined and where.
Where is that described.

Follow up question, how do I make the email column display the actual email address (intended for the super user only).

The name fields are based off the name style you've selected in CB > Configuration. Suggest reading the CB Primer Book, which you can download below as it goes through CB configuration and explains the parameters.

www.joomlapolis.com/downloads/documents

Thank You,

I did read the the CB Primer Book. However, it does not describe how the different name fields are handled/connected.
Nor how to list the actual e-mail addresses.

The note on page 41 explains name fields. This section covers explaining fields in general. Page 103 explains CBs configuration page where you can adjust things like the name style or how the email field is displayed. Please review carefully and read parameter tooltips for further explanations.