Wow, Yeah I guess there really are quite a few versions. That's a Moog lead BTW. I' have a bunch of ELP .mid files. Had to edit corrections to just about every one of them though. I will tell ya one thing, don't judge a .mid file by its intro on the net. The intro's are commonly the finest authoring of most works. people get lazy, plus the kids, the wife, the in-laws...you know. If a professional does all the work,it is likely to be much more complete and there will often be more substance and polyphony. Use an app that prints .mid files to new standard staffed music notation. Many do.
MORPH!