I identified an issue that could break the game. To make things easier so you don’t have to restart anymore, I removed the checkpoint from that last section, and now it will start from the previous one. The path to the ending will be a bit longer, but there will no longer be a chance for this bug to block Ending 1. You can continue with your current save, and it should now work.
I’ve just uploaded this version, and it’s now available to download.
Sorry about that.