They guy (if I understood correctly) simply said to go to one of two IP addresses (for me, 192.168.1.1), log in, then go to the webpage which lets you pick the firmware image - which I did, and provided a screenshot.
Are you talking about the bit about turning off the router, keeping the reset button pressed, turn it on again, keep reset button pressed for 15-20 seconds, then release? All that did was make the router not show up on my computer (i.e. the router was on, the LAN LED was on, but the WLAN LED was not), then I had to turn off and on again normally, and pull out and back in the LAN cable for it to show up again.