From my understanding, vanilla raws (i.e. the raws that you download directly from the official site) haven't worked for around 50 turns now. The worst part is, once every few turns, the modified raws turn to blender. A few have mentioned this results in weird icons on that map. Thankfully, it's not gamebreaking, but it does break the diacritics and the ability to unretire or embark as a human civ. I haven't modified the raws at all, I just copy-pasted and turned into a rar the last stable raws that kept diacritics and ability to embark/unretire as human civs. I often test them myself to see if they break the game in the current state, but thankfully, I don't get issues. The biggest issue is unavoidable, that of save size bloat at every turn, but that's likely because of the site files whose increase every time someone makes a new fort or upgrades an old one and it's understandable.
I am almost 100% certain that after my and Avolition's turns, the raws work exactly as they were left, but tracking down where they get borked is something I have not been able to do. I'm not too technical-minded; my best guess is that it's someone replacing the graphics, either manually or through LNP and that has a cascade effect on the raws for some reason. I use phoebus and I know that after ending a turn and testing the save, I don't have issues. I don't know what he uses, but I know if Avolition has unborked raws before his turn, he also gives a save with unborked raws. That's the extent of my observations on this weird phenomenon.
Or maybe it's an operating system or something other that throws the raws into a blender? I'm just guessing here.