There was a bug in Robot Builder that caused C++ code to compile fine, but not load on the robot. It made me realize that debugging by deploying code and rebooting the cRIO is not enough.
Use the FRC instructions to set up your C++ (
http://wpilib.screenstepslive.com/s/...iver-workbench) and then follow the debug instructions (
http://wpilib.screenstepslive.com/s/...-robot-program) instead of deploying and rebooting. You'll be given lots more information and will not have to guess about what's happening. Once you have confidence that things work, you can switch between deploy+reboot and debugging as needed.
It is more difficult to get going, but if nobody on your team can get debugging to work, you're going to have a very rough time with C++. It's not too late to switch languages!