Glad you're enjoying the aircraft!  I hope you don't mind if I answer in a list.  Lots of messages to get to today!
I assume you mean during dawn/dusk hours?  Yes, I very much do not like the interior lighting in MSFS 2024.  I put a tremendous amount of effort into my night lighting, because flying at night is possibly my favorite thing in the real world.  MSFS 2024's daytime lighting and automatic exposure compensation will pretty much defeat any nuance that I add, and all results disappoint me.
I have no control over this, so your answer lies elsewhere, I'm afraid.
Same as above.  The navigation/GPS code is identical on my side between the two simulators.
Indeed, I have a new magnetic compass effects simulated in these aircraft.  Assuming we're still talking about the Baron, that large of a deflection is likely to have come from the hot-plate, directly behind the magnetic compass.