I wonder if there's more to it than that. My daughter has been pulling her hair out for the past 2-3 months because she couldn't download on her iMac upstairs, while I had the same problem on the PC in the office. We've been behind a router for longer than that with no problems, so I don't see that the router settings alone has anything to do with it.
Anyway, I've been working on a project out of town recently and staying in a corporate apartment. The setup there uses static IP addresses and I tried Limewire 2.9.8 again last week. Great results by comparison. The success rate was around 50%. Today I'm back at home and have had one success after 20 attempts. So I'm wondering if Static IPs vs DHCP may have anything to do with it.