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The one thing I'm having trouble with is making/creating the .mpk-extension file for my attempted mods. I'm not doing anything epic, just trying to do some balancing, and I can unpack the files by converting copies to .zip (by literally renaming the file to .zip extension), but can't seem to get them back to .mpk the same way. Nor can I find any obvious programs to do the same thing. As such, I'm basically stumped. From the discussion it doesn't sound like there are any .mpk builder apps in the wild, so how do the rest of you do it?