Calling function associated with a button

[Heime]

I want to have a set of buttons and labels (placed into three columns) that 
execute particular functions when the buttons are pressed.  

Things have been going well, except when I try making moped call the appropriate
entry in the functions lists (fc1-list, fc2-list, fc3s-list) for each button.

(defun moped (monbf fc1-list fc2-list fc3s-list lb1-list lb2-list lb3-list)
  "Insert three lists of labels into BUFFER-NAME in three columns."

  (with-current-buffer (get-buffer-create monbf)

    (erase-buffer)  ; Clear the buffer before inserting new labels
    (insert "\n")

    (let* ( (max-rows
              (max (length lb1-list) (length lb2-list) (length lb2-list)))
            (spx " ")          ; Space following button
            (kwd 13)           ; Column Width
            (zwd (+ kwd 4)) )  ; Empty Column Width

      (dotimes (i max-rows)

        (insert spx)

        ;;--------------------------------------------------------

        (let ((lbv1 (nth i lb1-list)))
          (if lbv1

              (progn
                (insert-button "[-]"
                  'action (lambda (b) (nth i fc1-list)))
                (insert (format (format "%%s%%-%ds" kwd) spx lbv1)))

            (insert (make-string zwd ?\s))))

        ;;--------------------------------------------------------

        (let ((lbv2 (nth i lb2-list)))
          (if lbv2

              (progn
                (insert-button "[-]"
                  'action (lambda (b) (nth i fc2-list)))
                (insert (format (format "%%s%%-%ds" kwd) spx lbv2)))

            (insert (make-string zwd ?\s))))

        ;;--------------------------------------------------------

        (let ((lbv3 (nth i lb3-list)))
          (if lbv3

              (progn
                (insert-button "[-]"
                  'action (lambda (b) (nth i fc3-list)))
                (insert (format (format "%%s%%-%ds" kwd) spx lbv3)))

            (insert (make-string zwd ?\s))))

        ;;--------------------------------------------------------

        (insert "\n"))))

    (pop-to-buffer monbf))