https://code.google.com/p/rogue-code/wiki/ToneLibraryDocumentation
here it is, I think the problem may be in the .cpp, and not identifying the mega 2560,
changing this:
#if defined(__AVR_ATmega1280__)
to this:
#if defined(__AVR_ATmega1280__)||(__AVR_ATmega2560__)
might have fixed it, I'll test it this afternoon.