The monsters can as I mentioned in an earlier post be controlled by captain Noctilus of the Bloody Reaver if he is present on the table. It's an excellent way for the bad guys to increase the number of "Auxiliary" miniatures in their service. The sea monsters are also a lot better than the auxiliary ships, dirigible and dragon.
I also made a customized transport box for my Dreadfleet collection. I took the Dreadfleet box, and cut old Feldherr army bag inserts in half and used them to create folds for the ships, cards, tokens and everything else except for the terrain pieces which there wasn't room for. All ships except for Heldenhammer can be transported standing upright even if the lid is closed If it wasn't for those pirate flags, the Heldenhammer too could have been standing upright, but now I had to lay it on the side. I made sure there were pieces of foam supporting the sails from both bending and scratching the bottom of the box.
It's not very pretty, but it's functional. I actually made something similar to transport most of my By Fire & Sword collection as well.
If you have some cash to spare, there are original "Dreadfleet" inserts from Battlefoam, though they call it something with "sea..." and not Dreadfleet. Those inserts have room for all the ships, terrain and extra pieces.