The media pack needs to install to the same location as the main mod installed in, so it should be something which ends with /mods, just like when you installed the patch & game.
Creation Mapscript would be saved in the Public Maps folder (right beside the Mods folder), as for other scenarios I am not entirely sure. I think that so far most of them are worldbuilder saves, so I guess the quickest way to find out would be to save a game in worldbuilder and then do a quick search of your harddrive for that filename (make it unique).