Just to clarify on this topic (though I see you've found the solution already), the zip file inside the outer zip file is not a valid zip file -- it's some sort of special format used by AppLife, the updater component that we use. Why they gave it a .zip extension I don't know, but it's not really zip (or maybe it's encrypted or something, I really have no clue). As the text file in the outer zip notes, and as you clearly discovered, simply uploading the outer zip file (the whole package that you download) into the Manual Install button in the updates tab of AI War will handle everything for you with no worries!
Glad you got it working!