I am trying to upload to my nano the code attached. It is giving me an error saying variable must be const about something I am trying to put in progrem. I learned that installing a older version of the compiler worked. However I was wondering is there a way to just edit the code to make it work. I tried putting const before it but it didn't work. It is on line 78 and 79 of the first file.
const extern PGM_P *NApowerCodes PROGMEM;
const extern PGM_P *EUpowerCodes PROGMEM;