I'm learning to play this early Glass piece so I thought I'd make a video version. No, this is not me playing it, this is a sequence I did with Cubase. And it's playing back at twice the tempo as Glass' original recording from 1975. I primarily sped it up so it would fit within YouTube's 10 minute time limit (which was their policy at the time I originally made this), but actually now I really like hearing it at this speed. And since I'm not aware of any tempo indication on Glass' original score (and much of his music in the 70s WAS played at tempos approaching this speed), I feel that this is a justifiable choice, though you're free to disagree of course. I definitely couldn't play it live this fast, though. It's hard enough to keep it together at half this speed.
In any event, this version is mostly meant to be more of a technical illustration of how such Glass pieces are put together and notated. Hopefully you'll find this useful in aiding your appreciation of this music, which is admittedly an acquired taste for most folks. I highly suggest you seek out the original recording, which is easily available on CD. Or better yet, catch a live performance sometime- you really can't truly appreciate this music unless you hear it performed live, as it was originally intended to be heard.