Please help me identify some cowries I found in Mozambique?

[Song Sprite]

Hello, I hope that you can help me identify these shells. My local library only has one book on seashell identification, and it does not cover these shells. Any help would be truly appreciated! I found these all dead and some are in very poor condition or just under-fossil, but I have enough of the same types that I hope we can still identify them. My apologies that the photos are a bit dark. I believe I have 5 different species, and I have indicated them by numbering since I don't know their names.

1. Large white shell with red-orange inside
2. Medium green shell
3. Small white shell with green top

1, 2 and 3, top view: (please note that the two smaller shells are green colour, the picture just doesn't show it very well)
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_183139.jpg

1, 2 and 3, bottom view:
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_183222.jpg

1, inside:
[/url][url=http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile Uploads/20140227_183318.jpg]http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_183318.jpg

4.  White shells with light orange/cream banding on top, small lighter brown spots on top, and fewer, larger dark brown spots on sides. I believe the shells in this photo are all the same species. The three shells on the left are partially under-fossils (the upper layer with the spots has worn away on top).

4, top view:
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_183444.jpg

4, side view:
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_185919.jpg

5. White shells with purple top with light orange spots and yellow-orange stripe on each side (the ones where the orange stripe is missing are under-fossils).

5, collection:
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_190531.jpg

5, close-up of two shells - the one on the right is the only fully intact sample I have:
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_190628.jpg

5, another view with better light:
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_190712.jpg

and
http://i169.photobucket.com/albums/u220/Song_Sprite/Mobile%20Uploads/20140227_190736.jpg