It sounds like they've blocked you good. I haven't had any experience with such large "security" measures, so I would not know how to fix this. But I do know that Force IP will only work if your firewall accepts forced ports. I think you can rule that out as a possibility, though. I'm sure they wouldn't want to leave a loophole for you to jump through.

The fact that none of the Gnutella clients work for you indicates that this is not a LimeWire problem. Sorry I can't be of much help. :-(