I just wanted to put this out there in case anyone is having similiar problems with XDebug running in Netbeans 8. When I was stepping through the code in register.php Netbeans running XDebug debugger was reporting a 'value not available' or some similiar message on the form validation pass, line 98, [First Name].
When I chose Run File from Netbeans (without the debugger) everything worked fine. This appears to be a case of XDebug acting buggy. I was running it with the Debugger to resolve file locations, db name, passwords, etc., just to get the script working. Hope this saves someone some time.