1.
LibSharedMedia-3.0 is the library that addons use in order to access textures, etc. outside of the addon itself (in other addons, texture packs, etc.) In order for an addon to have access to this pool of media, it must request it from the library. In order for an addon to add media to LibSharedMedia-3.0, it must register it with the library.
SharedMedia is an addon which stores extra textures, etc. SharedMedia then registers all of its media with LibSharedMedia-3.0 so that addons may access it.
2. Read "Instructions for MyMedia.txt" inside of the SharedMedia folder.
3.
SharedMedia is an addon which houses extra media to add to LibSharedMedia-3.0.
SharedMedia-2.0 is an outdated version of SharedMedia (despite it having 2.0 at the end - long story).
SharedMediaAdditionalFonts are extra fonts to add to LibSharedMedia.
SharedMediaAdditionalFonts-2.0 is another version of SharedMediaAdditionalFonts, left over from when SharedMedia and LibSharedMedia were going through changes. Actually, I'm not sure which is the current/correct one to use...
SharedMedia-Blizzard takes textures from inside the game and adds them to LibSharedMedia-3.0 for addons to be able to use.
LibSharedMedia 3.0 is the actual library (see #1) that addons use (you don't need to install this).
SharedMedia_MyMedia is what is created when you actually read "Instructions for MyMedia.txt" in the SharedMedia folder.
4. See #2
5. The
smoke artwork can be added by any addon that adds art to the game. kgPanels uses LibSharedMedia, or you may import the art directly into the addon via it's in-game options (there are in-game instructions also). Or you may use something like BTex or Sunn Viewport Art (which don't use LibSharedMedia) to place the artwork at the bottom. The
minimap is SexyMap - that texture is one of its skins. The
unitframes can be recreated using a flexible unit frame addon like Stuf or PitBull4 and using kgPanels for the artwork.
/edit: MM55 beat me!
/edit2: I blame my cold medicine