I've so far only ran into them in two of the canal works in Vivec, Redoran and St Olms (also in the St Olms storage which is off the canalworks), so I cannot verify that this occurs elsewhere. When a bonelord is killed, it collapses on the floor and is lootable. After leavingthe area and returning once or twice, the bonelord is standing back up. It is still lootable and npcs don't react, it just looks wierd. very minor I know, but just wanted to report it. there are screen shots at the link below.