So in other words you intend to have people attempting to download files from you at zero speed. WOW what a nice person you are. Some people I am sure will think you are belonging to the RIAA, etc. & will ban your ip because they will think you are offering fake files. I hope you realise what a pain you will be for people out there. If you don't wish to share then don't. But don't be a nuisance on the network by pretending to share files that people can't get. Not too many people would disagree with me on this point. It sounds to me like you have set yourself the wrong Connection Speed if you can't control upload speed properly. But then you hinted your intention is to offer ZERO upload speed.

LimeWire is p2p (Peer to Peer); sharing between 2 or more people. Some people are so so selfish & greedy & in your case totally inconsiderate of others. What fun it would be if everybody set their upload speeds so zero. Then NOBODY would get any files to download. And why should anybody share with people who are not willing to share. In some cases there is pressure from ISP's but this is not the norm.