I'm just playing through TTB now, and I encountered the same issue, I was able to fix it by turning on V-Sync inside the video options after I launched the game.

There's a bug at level 13 where you enter the elevator, the game crashes for no reason so you can't progress to the next level.

I was able to finish TTB on Windows 10, I don't recall having an issue with that. The only thing I can recommend is try changing some of the audio and video settings through the external setup or in-game, like toggling different options like EAX or vsync, i.e. turn them off, try to exit the level, if it crashes then turn it on and try again.

I think it's because you have the gog version and i played a patched freeware version. Thank god for archives since that was delisted.

I have another solution. Can you make a save point when level 14 begins on hard mode on a good mortality focused playthrough?

I did a good morality play-through on easy or normal, I don't remember which. Here are the saves if you want them, there's one for the start of each level:
https://www.mediafire.com/file/y4r2auv8igakztw/The_Suffering_TTB.zip/file

ok thank you so much you are a legend. (I found the actual solution. In the levels file [Level 7] all but the industry.dat were missing in the folder so adding the rest of the intended files fixed it)