Whoops, it's been a while since I posted in this thread.
miniboss / ambush theme: That remix sounds remarkably similar to the original, so pretty accurate, both from the standpoint of transcription, and instrument choice. Not a very complicated song, but a fiathful transcription nonetheless. Definitely preserves that sort of creepy-ish feeling.
Hawkeye's theme: Once again, this is a pretty faithful transcription. This song is a bit more lively than the other one, so a bit more enjoyable to listen to. In this case, some of those NES instruments are a bit harder to faithfully synthesize with ORGMaker, but this is still a good transcription nonetheless.
Iron Pipe: So, first off, not a bad transcription, and with this being a more sophisticated song, it can be harder to really do it justice. But you asked for feedback on what you could have done better, so I'll give some feedback on that. If I had to think of one area where this could be improved, that main instrument track at the beginning seemed a bit high-pitched compared to the original, and it just didn't come off as strong as in the original. The original just has a stronger and more vibrant introduction to show that it means business, and I feel as if this ORG could be improved to better capture that. Maybe something that can be changed more broadly is that the original conveys this with sort of an "electric buzz" kind of sound in some of its instrumentation, and that's something that seemed kind of lacking in this ORG.
Mt. Blaze: Yeah, I feel you, making a chiptune remix of non-chiptune music can feel awkward. At the opening, it did sound a bit weird and sparse, but once it progressed some more, it started to sound pretty nice once more instruments started blending together. I feel as if more could have been done with ORGMaker to synthesize some of the background instrument sounds, but again, I know that remixing non-chiptune music can feel weird.
Smurfs (NES) Boss theme: Pretty simple song, so naturally, simple transcription. The instruments and tune sound pretty similar, so not much to say. It's a pretty faithful transcription.
Act 05 The Flight on a Stork: A bit more of a lengthy song than the previous. This one also is a pretty faithful transcription, both from the standpoint of tune and instrument choice. Sorry to hear that the gold mines transcription attempt didn't work out.