I'm not sure if it will make a difference, but you have mIRC in there twice ... once with a single port, once with a port range that includes that first port. That conflict could potentially be the problem. Just remove the 6667 (single port) one. Also, make sure that you are the computer that has an IP ending in 100.
Also, I'd recommend forwarding the identd port (113) on TCP as well. It probably isn't the problem, but it still makes connecting easier on various networks.
