Speaking of damaging wheels, as long as the hook has a good rubber coating it shouldn't cause any scrapes. The two damaging thing I have seen customers do tends to be on wall hooks, not ceiling hooks, though ceiling might be possible if unlikely. One that happens is hooking the valve stem and blowing the tube. You can also damage the spoke nipples on wall hooks if it is in contact with the hook while hanging, as long as you rotate the wheel so all the tension is going to the rim you should be good.