AVR-GCC warning extra tokens at end of #undef in porthardware.h

Until now I haven’t tested it with a demo, only with my own program.
Maybe that the demo is configured for another timer as FreeRTOS tick timer.
You have to set the RTC as FreeRTOS timer. Have you done this?
If not you can do it by setting configUSE_TIMER_INSTANCE to 5.