Oops, I just posted a thread asking for help on this piece and didn't notice this one! Anyway, if you see my thread, I too am having a lot of trouble with the 32nd note runs. My biggest issue is playing the scale. If i do it at full tempo, it sounds messy and very uneven.
For whatever reason I can do octave glassandi quite easily. All I do is play and octave and drag my hand, and it comes out just fine. I put quite a bit of pressure on my pinky in order to hit the notes, but much less pressure on my thumb to avoid hurting it, since it's dragging backwards. Probably something to do with the way my hands are shaped, though. If you're having trouble, it might actually be easier to play it as individual notes, as some pianists do. Personally, that would be much harder for me, but it might be easier for other people.
Another factor might be your piano itself. If you're playing a piano with heavy action, you'll need to apply a lot of pressure to play an octave gliss. This might cause your fingers to hurt until you toughen them up and get more used to it.