I've been trying to set up a server that uses naval units, but they error out for human players.
creating/loading a Naval unit timeouts the server.
When deploying, they are given -elevation equal to the depth of the water. Doesn't float.
Movement can't be done because the unit is "under" the water.
Firing can't be done because weapons are "under" the water.
Bots CAN use naval units with no error.