If the lockpick are not in either table (should be in the left one, IIRC), try re-installing the patch; that may put them back. Before the 1.32 hotfix they were breakable, but the hotfix would return them to the table. In games started before installing the 1.34 patch, they would disappear if dropped on the ground.
First try deleting all of the files in the '
..\Divine Divinity\Run\Dynamic' folder.
This folder is used as a cache for the game. Files are created / copied there from the save game folder when you load, and written / copied from that folder when you save a game. The files will be re-created as required the next time you start Divinity. If there was a corrupt file in that folder, deleting the files should fix the problem.
If that doesn't help, see a reply to
Lost Items - guide and directory of inventory files.