The logic is that this work seems to be something that WOULD fit in a Castlevania Chronicles kinda idea (a retelling of Simon's adventure, for instance), but, as the definition of apocrypha says, the game is either "of unknown authorship, or of doubtful authenticity, or spurious, or not considered to be within a particular canon."
Whoah! That's just amazing how deep you're understanding this idea. Everything that you said is absolutely true. I think I can't use an "Apocrypha" word directly, but now I have a good direction. Thanks a lot!
Oh, and I've listened the soundtrack you gave me. Well... It really misses almost all low-tones, IMO. That's the common problem of many arrangements. The "deepness" of the original OST is maybe the most valuable feature for me.