You're welcome! Without giving too much, the subtle things were like occasional visual ques that are hard to catch (bathroom mirror for one), certain sounds you thought were for one thing weren't actually from that (like when you picked up the key, there are two separate sounds, one of which is not for the key), or other small sounds (apart from the ambience) that you didn't seem to notice, but had an affect on the world. Since it's very dark, sound is very useful in the game, so pay attention to some of those. You were a bit over halfway done though.
Thanks for the compliments too! I'm working on two projects right now, though one is on hold so I guess I'm currently working on just one, but I do plan to release both. And yea, I am very busy so it will take awhile until something new is put out by me.