Illarion.org

I looked at it again and it said that client.exe was needed for opening ZIP files.  I didnt read that before.  Something must be wrong with me winzip

I downloaded illarion and i clicked on it in my directory and a window came up and said
' Windows cannot find client.exe' and then it  had a box to put in its location.  What is wrong with it?  What should i do?