item's themselves don't do anything. You make item abilities and give them to the items, which are cast when you use the item. You can set the charges an item has in the object editor under the item tab, zero charges gives it infinite charges.
Yeah, like.. for heal from hp pots do heal instantly, while the regeneration pots, like scroll of regeneration are 'non-combat consumables' which stop working once you get hit by something.
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.