I suspect that paying the 30 bucks gets rid of the 5 host limit in the display window. The WEB site shows more than 5 hosts being displayed. Too spendy for me to test that theory :-(
A few warnings on the Console don't seem to matter:
2009/06/03 7:30:58 114-47-202-105 IP Scanner[12987] Warning *** NSTimer ignoring exception '*** -[NSCFArray objectAtIndex:]: index (34) beyond bounds (34)' that raised during firing of timer with target 0x82be00 and selector 'doCountdown:'
IP Scanner
Displays machines, Mac users, IPs on a local network.
Version: 2.34