Yeah, I've heard those rumors about it possibly coming to Broadway, I hope they're true. I don't have the soundtrack. I was trying to get it for a while, they have used copies on amazon now starting at around sixty dollars, but I'm not sure I really want to pay that much for a cd that's not even in english. lol. I actually posted a thread last week in the motion pictures, animation, etc. section of the forum asking anyone if they knew how to get the mp3 files online or something, but no replies. Hopefully it will come to broadway in the next few years, then we'll have the soundtrack in english!
As for the phantom sequel, I've got to say I don't think it's such a good idea. It just seems kind of, I don't know, fanfiction-y. I don't really know anything about it, though.