For some reason it didn't want to start while having it open in my browser, but after downloading it worked fine. I like your implementation! And about people not leaving any comments or anything: it happens. It could also be because people aren't logged in, but when it happens, one's just got to deal with it, I guess.

The problem is that here on the site, the user does not have the benefit of using the Greenfoot IDE to move the ships into the grid. You will have to program that into your project to allow them to do that while the project is in a running state.

Thanks for your comments @SPower and @danpost. I cannot test any game online (damn Chrome), That's why I give the code, to run it offline.

One problem I noticed: I fired the last shot at the computer's last ship, but before it gave the win screen, it let the computer take its turn, and in that turn it killed my last ship, and said I lost. something small, and probably rare, but maybe worth looking at.