I know it's a bit late, but I solved the same problem on windows 10 (crash during Sumiko's ending)
I've checked all possible subreddits and forums, but nothing worked (windows' capability, in-game settings, reinstallation from other sources etc)
So the last thing to try was the Virtual machine. I've run the same game installation on windows 7 and everything was alright
I know setting up the VM takes a lot of time, but once you do it you won't have any more problems with any of the old VNs