Modifying your LimeWire props file doesn't help you at all since you are accepting at least 30 leafs by default. It's just a guess of course but an ultrapeer should have at least 50% incoming connections. Since a lot of ultrapeers don't seem to accept incoming connections I usually see 80-90% incoming connections. Since you had only one incoming connection out of thirty connections it seems that you don't accept incoming connections from everybody (maybe only from peers with the same ISP???). Leafs that try to connect to you probably can't since you (your firewall / your ISP) are somehow blocking them. With the new high outdegree network it does not really hurt if some ultrapeers don't accept leaf connections, they can still carry a part of the network load by forwarding queries between ultrapeers.