I just unpacked the archive and repacked it using Windows Compressed Archive as per the instructions but the zip file is the same size (that thread says it should be about half the size). I'm guessing the Steam version of the game already has this "patch" that thread was talking about. That thread says to expect loading times of 12 to 20 seconds and I'd guess that's about what it is for me. Though I haven't run Torchlight in a while so I'm not sure.