So, you're saying I should declare all my library-specific variables in the .cpp file, instead of .h?
extern HardwareSerial Serial; // so it can be referenced in lots of places
// actually create the object: HardwareSerial Serial(&rx_buffer, &UBRRH, &UBRRL, &UCSRA, &UCSRB, &UDR, RXEN, TXEN, RXCIE, UDRE, U2X);
Why can't they fix the issues with the files?
And if I don't want them to be global to the entire sketch, I don't prototype them with extern in the header?
It would be ideal to be able to have the ISR call functions from inside a class. Is that possible?