This is the routine I wrote (I don't use the panel yet). The array definition is at the top of the file.
Well, that's just ducky. You don't suppose that we need to see it, to confirm that the code is accessing the data correctly?
All I get is garbare, not what I expect and get when not using PROGMEM and pgm_read_byte (aka a simple array).
We can't confirm that you are reading the data correctly. In fact this statement implies that you are not. Without seeing the declaration, all we can do is wish you luck.