Thanks, Kindlevarazs!
I changed the Navpoint tags in the nxc file but am still getting errors.
<Navpoint id="begin" playorder="number1">
These are the errors I'm still getting from KindleGen:
1. 'Info(prcgen): Atleast one <navPoint> tag mus be there in ncx file.
2. 'Info(pagemap): No Page map found in book.
Any ideas?