Of course with only one WAV song loop, the Elastique can not make the miracle!
If for each chord pattern we can drag multipe different instruments loops and for each you setup the Root pitch shift, this will automatically resolved.

If you hate DJ stuff, is another story.
In the qranger editor allow to record any type of styles, Audio-midi in sync.
when my webserver come up again, I will shown you hot to make one Jazz swing midistyle:
import one EMC midistyle, deleting the shitty midi Drums tracks and add the Real Audio drums brush or the all midi tracks that you hate.
maybe you never saw how to editing with the qranger: http://youtube.com/watch?v=yYM5IdJvJW4
What you record there; the Mediastation arranger will Play, no more...all depend on your composing fantasy and under qranger is really all easy to do.
If then you still like the only standard midi styles system and add in your system one standard PC paltop for play Mp3, this is another story.
Enjoy what you play..