As best I can tell you can recreate the problem by deactivating the plugin and dropping the tables from the database with wp-dbmanager plugin (i do this when i no longer use a plugin).
Bora kama naweza kukuambia unaweza recreate tatizo kwa deactivating Plugin na kuacha meza kutoka database na Plugin wp-dbmanager (i kufanya hivyo wakati mimi tena kutumia Plugin).