Saw this was bumped and actually took the time to try the game (thanks for the recent upload, by the way) since I always liked the CG collection that was on exhentai. Currently banging my head on the wall trying to figure out how to unlock all of the events - there's no option for it in the gallery with the English patch that was located in remicks' link, which I gathered was already known (the patch takes the game back to an earlier version). Deleting patch202.xp3 reverted it back to v1.14.9.23, at least according to the title screen, but there's still no unlock option in the gallery menu and I'm almost certain that's the latest version.
Finding another upload of the game on the web that hasn't been English patched (so I can test it and see if that would let me use the gallery unlock) is proving to be surprisingly difficult for me, so I guess I'm going to have to enjoy what I have right now. I've unlocked most of the scenes without too much difficulty, though the more advanced ones are eluding me thanks to my ineptitude at trying to play it normally and my not so great skills with Cheat Engine - I know how to raise each girl's H values, but not so well that I can figure out the addresses for all three in time before the final girl shows up.
If anyone stops by and can even just upload a save that has all of the gallery unlocked, I'd love you forever. If I manage to come by one, I'll post it, too, since all of the old links seem to be broken. I don't know why, but every link to mega that's more than maybe four months old never works, and I assume they did something to the site to change how everything was linked that broke all of the old ones.