Inserting string to start of mode-line via change in mode-line-format

[Heime]

Wanting to insert a string (act) in the beginning of the mode-line, 
mode-line-format was
modified as follows.  But I am not getting the string printed.  What am I doing 
wrong here?

    (setq-default mode-line-format
                  '("%e" mode-line-front-space
                    (:propertize
                     ("" mode-line-mule-info
                      mode-line-client
                      mode-line-modified
                      mode-line-remote)
                     display (min-width (5.0)))
                    mode-line-misc-info ;; <-- HERE
                    mode-line-frame-identification
                    mode-line-buffer-identification
                    " "
                    mode-line-position
                    (vc-mode vc-mode)
                    " "
                    mode-line-modes
                    mode-line-end-spaces))

    (push '("" act) global-mode-string)