Re: Other potential problem with :format.

[Richard Stallman <rms@gnu.org>]

    ! An editable fields must be surrounded by static text on both sides, that
    ! is, text that does not change in the lifetime of the widget.  If the
    ! field extend to the end of the line, the terminating line-feed character
    ! will count as the necessary static text on that end.  You will have to
    ! provide the static text before the field yourself.  The @code{:format}
    ! keyword is useful for that, if you give it a value of e.g.  @code{"Name:
    ! %v"} the "Name: " part will count as the static text.

It would be clearer with this small rewrite.

    ! An editable fields must be surrounded by static text on both
    ! sides, that is, text that does not change in the lifetime of the
    ! widget.  If the field extend to the end of the line, the
    ! terminating line-feed character will count as the necessary
    ! static text on that end, but you will have to provide the static
    ! text before the field yourself.  The @code{:format} keyword is
    ! useful for generating the static text; for instance, if you give
    ! it a value of @code{"Name: %v"}, the "Name: " part will count as
    ! the static text.

Can you install it?