Haven’t got that issue, but always when loading save game; the location flashes through Open Sea ‘avomeri’. If believe that’s just the map loading (with 0,0 coordinates at top left) and like you’re postulating: where your game load crashes.
Have you tried with older version install, say 3.52, with same save games? Or where those where you older characters are from?
Another thing that comes to mind: I got a feeling that you can create a new character, but when you start playing that character, the game freezes?
(Just trying time help/understand/clear the issue... I like to keep Sami busy with Suggestions...