Need help with Multi-Dimensional Arrays

[johnwasser]

@mrariez

  //For some reason this won't work
  sendRAW_Flash(CoolMode[CoolSetting], signalLength, khz);
  //But hard coding the index does, I can't figure out why
  sendRAW_Flash(CoolMode[5], signalLength, khz);

That's because you put your array in PROGMEM but didn't tell the compiler to fetch the contents from PROGMEM.

When you use a constant, the compiler knows the address you put in your PROGMEM array and uses that address. When you use a variable, the compiler generates code to fetch the array entry. Since you are not telling it to call the function to fetch from PROGMEM, it fetches from RAM.
Try:

  sendRAW_Flash(pgm_read_word(&CoolMode[CoolSetting]), signalLength, khz);