The seemingly easy task of making truly numinous and eldritch music is in fact very difficult, as difficult as writing a really frightening ghost story. Both endeavours have been so overwhelmed in recent decades by the continued deluge of dissonant crashes and bangs on the one hand and endless vistas of slime and gore on the other, that listener and reader alike are now inured to all effect. True horror now demands a command of subtlety and delicate implication rare in both literature and music. The only works I have read which come close to it are the ghost stories of M.R. James; these are true generators of the cold frisson.
Anyway, you haven't done too badly here. Parts of it are astonishingly reminiscent of Frank Bridge's "Gargoyle" though, and at one stage I thought I you were going into Ives' "Celestial Railroad". I cannot say I was filled with unease or that I registered ominous portent, as I do with certain music, but the title implies a semi-serious approach, music about music so to speak, and in this aspect it is a thoroughly enjoyable piece of atmospheric playing.