Hi,
I had this same problem several weeks ago and i thought it has been solved but it just happend again. Every time I save something, the change won't last throught the saving process....it's like i didn't do anything at all....also people can order store items normally...weird anyway....
Here is a little screen-capture i made to make things clear - in this video i try to disable the store (which is quite important option I think =D)
http://dl.dropbox.com/u/20134432/prestashop.avi
I hope someone can help
Thanks