Oh my! You're absolutely right.

That last one should indeed say "
upper-left" (as that is most certainly the location of the compass on the world map screen)
Nice catch

Of course, no text in the demo is final (but close!), but if I'm to poke at anything and say "this is the least close to what I'd expect from a final release!", then it's certainly the Tutorial Text (text usually displayed in GREEN/Information boxes). Hilariously enough, some of its wonky-ness stems from the original Japanese version. Hopefully this isn't one of them

And, oh, also, you're absolutely right about the other thing too! The Technical Ring is indeed not an item you normally have at this point in the game. The hack that adds it this early in the game is very old and has been lurking around for a while internally, I believe. You'll probably still see the ring (in one form or another) already in place at the very start of the game upon the full release too. Possibly along with other little things (some of which you may have spotted already in the demo, if you've been thorough!) These things are there to enhance the game experience, add to the "localization aspect" of things*, some potential legacy bug fixes, aaaand... some that most of all serves to bring the game up to snuff with more recent releases.
*
No! I don't think you'll get different music for OP/ED! (Although, I have at several points said to Cless it'd be an awesome thing that he should do if we had the right talent available)