Hey, thanks for the patch.
A few things I found: first, the sex option don't actually match what happens when you pick them. For exemple, picking the blowjob option will actually trigger a paizuri scene. Second, and probably a bigger deal, picking the handjob scene causes the game do fade to black and time to progress as if a scene had played, but it doesn't. It also doesn't register the scene as having happened, as the handjob stat for the girls never goes up from zero, even if you trigger the handjob scene (which is actually triggered through a different option, as I said before). And apparently, from reading the troubleshooting section in-game, it seems development level will only increase if you do all the foreplay scenes at least once, which would explain why it's getting stuck at 38%.