Interesting....
First, some non-song items
Demanding that people listen to a entire 5-minute song before rating is asking a lot, considering the average attention span of a newgrounder. I like what you did in Cavern of memories, pointing out the good parts and allowing the listener to skip. I realize this is a older song, but just something to keep in mind.
Second, if mention ratebomers, you will only give the reason to rate bomb. I definitely learned that the hard way (if you are really curious, check my BBS history from a longggggg time ago).
However, neither of those items affected my review score.
Overall, I really enjoy this track. There are a few points in the song where I felt like the instruments didn't fit together perfectly, but generally, I liked it :D
0:08 You *almost* had the right lead coming it. I'm talking about the long noted lead. It just doesn't fit with the "foresty" atmosphere that you're trying to establish at the beginning. I could see it as a the start of a shadow, but its a bit too electronic for my liking.
0:42 the ascending sound you used to transition seems a little out of place. It feels very isolated with all the other leads promoting a peaceful forest soundscape, while this one gives the impression of "techiness"
1:38 The lead coming in literally made me jump a little. Maybe it shouldn't be as loud initially, or there should be some transition to tell me that it's coming.
2:25, the bg sounds really dominate the song here, which in my opinion shouldn't happen. bg stuff should stay in the bg. Fortunately, this domination doesn't last very long.
2:39 different hi-hat pl0x
3:38 I can detect a hint of distortion originating from the kick. I am not sure what is causing it, but it's barely noticeable. Just thought I'd let you know though.
Very good conclusion, I must say.
Since you have most of the fundamentals mastered, I just thought I'd show you a couple of details that you can watch out for in future songs. Good work!