Q,
Read through this thread: http://e2e.ti.com/support/low_power_rf/f/538/t/218578.aspx
I just recently had the same problem. Try to match up your UART registers with the ones I documented and check to make sure they are correct.
Also put a breakpoint in HalUartWrite and ensure it's actually being called. There are some case statements in there that prevent it from being called for me based on my port/alt config
Also, what do you have your IEN0, IEN1, and IEN2 set to?