Overwrite method:
Copy the following files to a temporary folder.
/data/
options.txt
keymap.txt
autopickup.txt
Extract the new version on top of the old version. When prompted, select “replace all”.
Copy the files you copied back to the new version.
Pros: faster, especially if you’ve explored a large amount of your world.
Cons: doesn’t leave the old version in-tact in case you decide you want to go back.
Transfer method:
Transfer the following files:
/data/
options.txt
keymap.txt
autopickup.txt
If you’ve edited any of the other files, transfer them, too. For instance, I always transfer fontdata.json (previously fontdata.txt) because I play with a custom font spacing for square-ish fonts.
Also transfer the folder:
/save
Pros: neat, complete, and under your control the whole way.
Cons: well-explored worlds can include tens of thousands of files, which means long transfer times.