Are there specific procedures for managing the built-in formula library so that custom equations don't conflict with the factory-set constants? I would love to find a detailed breakdown of the alphanumeric display settings to improve visibility when working under dim lighting. It is also vital for me to know if the device supports base-n logic operations directly through the primary function keys.

Do you use the Mode button to switch to the library or you try to access it via a shift command? I've been using this Casio calculator for about a year now and I couldn't figure out how to use it correctly at first either. If I calculate certain formulas, I always check if I'm doing it in the correct mode. I read the detailed service manual for CASIO FX-5500L on the ManualMachine website and found out that if the buttons don't respond at all, then most likely the shift key is activated, I often had problems with this. It also happens to me that it can give an error, so I just click on reset to factory settings and then it works again.