This.
Letting a softsampler deal with long wave files is asking for trouble.
Letting Cubase deal with it is - well, the better solution - but still not good.
Using Live, you can break up the song in its pieces; use different loops for the beats, trigger effects in time, and you can morph from one song to the other seamlessly because timestretching works very well (in Cubase you have to sort of announce it earlier). In case someone messes up it's no trouble at all to let something continue again, and when you'd pour everything in a single audio track in a softsampler you might as well just use a plain old MP3 player.
Halion? Is that even getting any updates nowadays?