Re:How Can I Fix This?
The short, glib, but, unfortunately, probably true answer is to stop using V-Vocal.
If you must use it, use it on small sections, print it out to a track and move on to the next section. Have a search through the forums for more workarounds. The bottom line is that V-Vocal is pretty buggy and prone to crashing Sonar, either find another way to retune things or learn the workarounds.