I know the whole thing now but I don't think I've gotten all the way through without stopping yet. Plus I don't have a full 88 keys to play on so I need to transpose down an octave in the middle of the piece, and even doing so I still miss a few high notes (rather than a lot of low ones).
And if my arms are getting worn out on my keyboard, I'd hate to imagine what will happen on a real piano. Oy. Well, maybe all this practicing will build up the muscles so I can eventually play it on a real piano and maybe pick up the tempo too.