Well, I'm almost done. I've got all but the last ending. I'm assuming that the last scenes I need in the 2nd and 3rd stages are associated with that ending. I'm currently out of ideas at the moment. I checked the homepage and in the BBS the creator put some hints on how to play the game. I roughly understand what he said. However it sounds more like general hints for the game than hints on how to finish the game. On the plus side, assuming I read it right, he's going to put a full guide on the website soon. In a post on the 2nd he said that he's going to post something (which I believe is the guide) in a week.
There is a patch out now. All it does is increase the amount of save slots from 10 to 20. Below is a direct link to the file.
http://kikenn.sakura.ne.jp/Kuroyokam...I0001-P001.zip