I just installed this and after figuring out that the download installs another installer that must be run I got it working.

First Scan so far detected over 2.4 million files - in the first two hours of scanning it has processed somewhere around 5,000 of those files - meaning that it should be done scanning the first time through in about a month or so.

In the first couple hours it has encountered 9 errors - all of a type unrecognized file format or corrupt file - the files which it has listed as unrecognized or corrupt are of the following types:

.gz
.sit
.dmg
.cab
.rar
.app ( Firefox.app )

granted a couple of them are Windows files - but they are on an external hard drive - and I do not see anyway to tell the app to scan only the internal hard drive - I think I downloaded the Mac only version of the software - however, at least half of those files are Mac OS files.

Since I started typing this message the scanner has picked up and is processing files faster than before - almost 40,000 scanned now - so maybe it will only take a week rather than a month to complete one scan.