I was about to ask if you were able to get the whole thing downloaded--didn't see that you had edited the post until just now. And . . . my day is now made. :) I'm really glad you liked it so much!
The level of surround is quite satisfying to me also--it isn't like The Incredibles or Batman Begins or an equally well made discrete 5.1 of that sort, but the Prologic II generation of upmixers really do a great job with matrix-encoded Dolby Surround tracks. The mono surround effects speak up when called for, and the rear stereo ambience gives a wider and more immersive sense of space than listening in two channels. (That's not to knock two channel, of course, because I've heard some truly impressive imaging from hifi stereo speakers, but my own system doesn't reach that level of excellence.) Jim Fosgate described it best when he said that the ambience is of a sort that you don't always necessarily even notice until it's turned off, at which point you really miss it.
I'm really glad to hear that the LFE levels are just right. I wrestled with them for quite a while, trying to bring them to a point where everything sounded as powerful as it should, but without being overwhelming. The levels in the SE mixes were all over the place--sometimes there was absurdly loud bass in places that didn't warrant it at all, and at other times inexplicably subdued where it should have been much stronger. The Star Destroyer was at such a low level I could barely hear it; I think even the '93 stereo had more bass than that! But all I really had to go on was an interview with Mike Minkler where he described the mixers' desire to achieve a "thunderous low end" for the passby, causing Steve Katz to invent the idea of separate LFE channels; and the recollections of those who had seen the film in 70mm and had the memory of the scene imprinted on their minds. Exactly what would have been considered 'thunderous' in 1977, when such bass effects hadn't been done before, wasn't exactly clear--it most likely wouldn't have been quite as strong as the sort of bass that frequently appears in films now, but what's in the SE versions couldn't possibly have been what they intended back then. I'm still sort of afraid that hearing the 70mm mix would show that my best judgement of what sounded good wasn't an accurate reproduction of the real thing, but I really am happy with the way this version turned out.