DLPB created a patch to make the sub game more manageable apparently, but I never had the slightest problem with it. What is it about the mini game that makes such a thing needed? Not to knock DLPB. I just want to know.
PS - if this seems rude or oddly worded, know that I'm typing this on an iPad having woke up at 4am and my brain doesn't fully work yet.
The game is quite playable as is (and I haven't released patch yet), however, it is extremely irritating as is. The Submarine game in PC comes from the Japanese original game revision, and not International or the western versions of FF7.
The key differences between PC/japanese original and the new is that that the original version has a slower submarine. Slower turning, slower ascent descent... etc. Go and play the game on PSX and then go and play it on PC. The Japanese original also has different placements and numbers of enemy subs. I am guessing due to negative reception of the sub game, they chose to change the programming for international/western ff7. I have simply restored the game to their final revision (although I didn't bother restoring the enemy sub data)
Also read my minigame thread, it goes through some of the changes more thoroughly. My patch also allows a person to opt to use my improved minigame, which adds specific difficulties to each level