Ahh the Dragon Rider. Didn't realize he could be resurrected 14 levels after he was killed. Good info. You have to be careful with him, he seems to go after everything, cows chickens etc. So I don't bring him near NPC's Another oddity about the Dragon rider, is you can't bring him through the teleport pads, perhaps the stones still work for him. Also he does not revert back to hostile when you leave the area like an average game monster. He also has very good site and will roam all over the place. He is better for confined areas.
With the normal monsters they will die when you sleep if they are under your command at the time. If I have 5 monsters under my command, what I do is cast skeletal wall and then place those 5 skeletons under my command which releases the monsters from my command. Though they are still freindly until I leave area. But if I don't take them with they will revert to hostile. So its best not to have your home base near NPC's in this case, else don't leave them in town.
The engineer can also be resurrected. He won't fight for you unless you place him under command.