I was able to edit/load the original files in 0.15.37 just fine. Seems that the ones you uploaded are truncated - they are identical to my changed versions, up until the end, when they abruptly end, cutting off the end of the file. Approx 1KB of script.dat and approx 32KB of level.dat is missing. G...

Yup, here's the original. Hex files were edited in Sublime Text 2, if that helps. All I manually changed was the fifth byte (possible that some "helpful" feature changed other things)

(files attached)

Followed rseding's advice here after downgrading to 0.15.37: https://www.reddit.com/r/factorio/comments/7fr9zb/update_on_01538/dqdw5cz/ I was able to edit the bytes in level.dat and script.dat, save, and view the save file in Factorio. The Base Mod was highlighted as the wrong version (still showed ...