I assume you're trying to edit the source of 1.6. If that's the case, make sure you download the correct one, labeled Source
And if you don't have it downloaded, download LÖVE 0.8.0 for you correct OS here: https://bitbucket.org/rude/love/downloads
Then, follow the guide here to extract the source: viewtopic.php?f=10&t=70
To recompile it so you can then play it, select all the files that are part of the source, then zip it into a .zip file. If you're using WinRAR, select the .zip option, and change the extension to .love
instead of .zip
Finally, run the game (the new .love
you just made) with LÖVE 0.8.0, and you have now just edited the game!
I hope this helped. :)