mzl / modifyzonemodel         Modifies an existing zone model

   Format:
      ;mzl <name> <number> <switches>
               Modifies a zone model <number> in the zonemap <name>

   Notes:
      Zonemaps are a plan for arranging windows on a workspace grid. Zonemaps
         contain one or more zone models, describing a region of the workspace
         and the kinds of window that region is allowed to contain.
      For a list of zonemaps, use the ';listzonemap' command.

      <switches> consist of the following optional switch options:
        -p <x coord> <y coord>  - Zone's position (in blocks) on the 60x60 grid
        -s <width> <height>     - Zone's size (in blocks) on the 60x60 grid
        -l                      - Single layer only (default: multiple layers)
        -c <corner>             - Which start corner (default: 'top_left')
        -o <orientation>        - Which orientation (default: 'vertical')
        -m <number>             - Maximum windows (default: 0 = no maximum)
        -v <number>             - Maximum visible windows (default: 0 = no max)
        -w <width>              - Default width (in blocks) (default: 0 = don't
                                     use a default width)
        -h <height>             - Default height (in blocks) (default: 0 = don't
                                     use a default height)
        -r <name> <type>        - Reserves the zone for window <name> of <type>
        -i <string>             - Owner ID (any non-empty string; first session
                                     to use the zone claims that all zones with
                                     that ID). If <string> is omitted, no owner
                                     ID is used
        -a <winmap>             - Default winmap for 'main' windows when
                                     workspace grids are activated (generally).
                                     If <winmap> is omitted, no default winmap
                                     used
        -d <winmap>             - Default winmap for 'main' windows when grids
                                     are disactivated (generally). If <winmap>
                                     is omitted, no default winmap used
        -g <winmap>             - Default winmap for other 'grid' windows. If
                                     <winmap> is omitted, no default winmap used
      If specified:
         <corner> must be 'top_left', 'top_right', 'bottom_left', 'bottom_right'
         <orientation> must be 'horizontal' or 'vertical'
         <type> and <name> should be:
            main                - 'main' (for any 'main' window)
            map                 - 'map' (for any 'map' window)
            protocol            - Any string chosen by the protocol code
                                     (default name is 'protocol')
            fixed               - Any string chosen by the controlling code
                                     (default name is 'fixed')
            custom              - Any string chosen by the controlling code. For
                                     task windows, the name of the task (e.g.
                                     'status_task'). Default name for other
                                     windows is 'custom'
            external            - The external window's name (e.g. 'Notepad')

      ';modifyzonemodel' can be used on a zonemap currently in use by a
         workspace grid, but the changes won't be applied until the grid is
         reset (using ';resetgrid').

   User commands:
      mzl / modzl / modifyzl / modzonemodel / modifyzonemodel
