As an example, you have a report for Windows Internet Explorer 8. When I look at it, I see 91 systems (all my XP pcs and some servers (I suspect 2003)). You omit IE 8 that is part of Vista and Windows 7 and Server 2008. So the count is NOT accurate.
Since this is your program, I think you should include thoses systems as well and perhaps have those systems in a different color which would indicate that the program cannot be uninstalled. This would prevent people from having to create custom reports in order to get accurate counts.
Thanks for a great product!