The only problem I had with moving my line of ships, was that one the the third rates would catch up with the second rate and those two wouldn't be able to turn very well. When I then issued an order for the group it messed up the whole line. The line that shows where your ships are going started at the side of the lead ship not in front of it. The lead ship would then turn around to try to get the direction correct and suddenly all my ships were curled up in a ball getting whooped by the French.