Garry,
Not so certain it's totally out of the question. From what I've read, the software that does convert .WAV to MIDI converts it as a single file, not individual instruments.That's what Jon was saying.
It may be possible to load the converted file into Edirol and enrich the sound of the entire orchestration with the addition of the "chorus" feature, but I'd think that would be the extent of it.
You'd then have to save it back as a .WAV file and create your own cdg using Kpro. Using Jon's analogy, you may be able to put some frosting on the cake
As far as adding intro's to existing cdg's you'd have to extract the audio as a .wav file, then create the new file to your liking, using an audio editor, similarly as I outlined above. You'd then also have to create a new cdg in Kpro.
That's the best I can come up with. Hope it helps, and if someone has a better way, don't mind hearing it. That's how we help each other learn
Take care,
George