We will look into it. It's difficult to swim while being a slave. Reported by Mollarom. The swimming is a side-effect of that. We will see what can be done.
Slaves now have a lower buoyancy, so they can swim better.
They are still light and will float to the top if left alone. Sometimes when a person is killed, their body remains there motionless instead of becoming a corpse. Thanks to DUdd for reporting. This seems to be accurate. Damned if I can figure out what's going on.