Larian Studios Forums Baldur's Gate III Baldur's Gate III - Technical & Gameplay Problems THE LAUNCHER HAS A DATA MISMATCH ERROR

I nuked my hard drive (accidentally), so did a full re-install and still have this issue on GOG also. I wondered if it were gog saves? Note, the windows system disk did not get wiped, just the data disk where I had the game installed.
When I got into the game, I have a premade party of dummies and (at least initially) polygons for my surroundings.