SomeFileName.mgs ( infact zip )

  SomeSkinFolderName/
                     SomeSkinFolderName.chm ( without this will create a default chm for you )
                     iconres.ezx
                     Some other skin files
                     svg/
                         Some flow files
                         Something.svg


note that mgs will extract to /mmc/movinand1/skins/

example:

     iphone_white.mgs

     iphoneWhite/
                 iphoneWhite.chm
                 iconres.ezx
                 info.ini
                 common.ini
                 ...
                 ..
                 ...
                 svg/
                     main_menu.svg
                     softKeys.svg
                     ...
                     ..
                     .
                 ...
                 ..
                 .