I ran into a bit of oddity with the latest version. I had been using tubes 3 and 4 for most of my fish and after some period of time (3-4 ships were sunk) I could no longer open the doors prior to launching the fish. As you can see in this screenshot I used the first tube after seeing that the switches to open the doors still worked on all other tubes except tubes 3 and 4 which I'd been using. Notice also in the screen when I'm moused over the switch it shows it disabled.
