Did you install first everything under Help, Install extra content, Download extra content, and then finally download and install proDAD Mercalli 4 (second go around) under Help, Install extra content, Additional program components? As I said, it's a 2-step process, not one.
Thanks John, I posted this and then I went back to the program and just happened to look at the Help Install extra content and saw it sitting there! I'm not sure what gets installed when you first download all the extras, but the scripts go one after another including Merc...4 and so I thought that was the installer. So I actually went back and did a Repair with the .exe but to no avail. I think there is a video somewhere around here that shows what we were in for after the purchase, a far cry from the demo that went so smooth without all the extra's:)