people say that maturity helps, but im 11 and i did it perfectly fine.
that tutorial showed ONLY the code for linksys, which turns out to be much different than most sites. my adress for setting this thing up is 192.168.0.1 instead of 192.168.1.1 so thats a big difference than what he recommended. if this is your code, heres what you do.
the first thing sayed is 4 links, click one that sayes status (that part i accually got the idea) i picked up the DNS code and pressed reconfigure, then advanced. there i saw tons of options on the left, i clicked port forwarding. if you dont have a text bar that shows the link code replace the link code with "blockland" because basically theyre the exact same thing. since there was no apply button i had to go next> next> next> so on till i got through to whole reconfiguring prosess, then my DSL line restarted itself. everything else was perfectly fine.
anyhow, that guy did say "if yours does not look like mine just click a bunch of links until you find something that looks like the next step." just do whatever he says!