I am having the same problems.
Got compile errors and had to replace:
WProgram.h -> Arduino.h
NewsoftSerial.h -> Softwareserial.h
The links below explain this.
After overcoming these compile errors I attempted to download demo-2.
The fat16 file in demo-2 would not unzip. I'm stuck at this point.
Any ideas??
So far I have not been able to play any files at all.
-Steve