I too can confirm that the Linksys WRT54G v5 breaks Pingplotter. I tried several different versions of Pingplotter on different computers on a network with the same results. After the first trace is made, it shows only the last hop - but the time in ms shows the first hop. Running tracert from the command line has no issues. This is not my network I was troubleshooting, so I can't send you a log. You might want to purchase one of the routers (v5), just to see for yourself. Very odd.