Two things. First about the tubes being screwy. Mind you I do not have a copy of the game. In "nautical land" even is port and odd is starboard. Maybe this got goofed this time? Or maybe there is conflicting ID numbers for the tubes themselves. Second the maintaining of 5kts to stay level. This sounds like the exact same problem that was present in 3 and 4. So hearing that I'm not holding out much hope for the fact that the boat will handle like a real submarine does.
Excellent and informative post though.