Got it running now. First difference seems to be the ship UI, seems more 'pushed back' and display looks smaller (same settings as Horizons), is this normal?
Probably - I'm not a good guide on that as I've not played Horizons since Odyssey launched, so don't remember if they look different.
(I'd hazard a guess that after a couple of play sessions it should seem 'normal' to you)
Enjoy EDO, there is a lot of new stuff to enjoy and annoy - just remember that 'grind' is self-inflicted...