I'm 60 hours into the original BG2 and in the beginning of chapter 6 it seems that the quest log is broken in a way that results in a number of done quests being erased, explored places being under fog of war and some upcoming plot points being untriggered, rendering the game unfinishable.

Is there anybody out there who has a save around the very beginning of chapter 6 that I could use?

Since after a few years of sporadically playing I'm not completely sure which mods I installed and I suppose that makes any outside save files working unlikely, I'll gladly accept saves for EE as well. My main character is a boneheaded fighter simpleton, chaotic good, that I imported from BG1, otherwise my party is Minsc, Keldorn, Jaheira, Imoen and Aerie. Anything close to that would be a plus. I suppose I can match my current gear with help of the console.

Hmm, ok, I found a save to the exact same spot on this site, and the party is quite similar to mine. And it actually seems to work as is, so I might use this.

I'll try my own save on another machine in any case first, if that would allow me to continue my own quest.

the thing is your build is busted and there is little point to moving on because it will just break again... thats the joy of mods mate

This particular installation and playthrough might actually be completely modless, I'm not sure. I tried out some but might have gone vanilla in the end. Anyway, trying out the save on a new install on another machine did nothing, so meh.