Please just overwrite your old folder with the new one! Or, alternatively, you can copy over the "data.json" and "throws, impacts, windups," and "decals" folders.
If you've already opened the new version, you'll need to copy these to another location as well. If you open your start menu and search "%appadata%", it should open a folder containing files for various programs. You should be able to find one labelled "karasubonk" where you'll want to copy those files to.
This consistent data location means that data will always be saved between versions now, so you shouldn't need to worry about it anymore after this version!