Ryan,
I downloaded your files and checked them out, taking note of what you did with what. I created an index.php that looked pretty much like your nuserver.php and created the appropriate functions. I can't seem to get past the authorizatoin step though. The QuickBooks Web Connector keeps telling me:
QBWC1012: Authentication failed due to error: Object reference not set to an instance of an object See QWCLog for more details.

Did you ever encounter this with your work?